feat: i18n 개선 및 userfront 로그인/로케일 보완

2026-02-12 21:25:26 +09:00
parent b6d3b69cda
commit dfa2fc2406
60 changed files with 5724 additions and 1734 deletions
--- a/.dockerignore
+++ b/.dockerignore
@@ -0,0 +1,18 @@
+.git
+.gitea
+.codex
+.env
+.env.*
+**/.dart_tool
+**/.packages
+**/build
+**/node_modules
+**/dist
+**/.next
+**/.cache
+**/coverage
+**/tmp
+**/logs
+**/*.log
+**/*.swp
+**/.DS_Store
--- a/.gitea/workflows/code_check.yml
+++ b/.gitea/workflows/code_check.yml
@@ -1,118 +1,125 @@
 name: Code Check

 on:
-  workflow_dispatch:
-    inputs:
-      run_lint:
-        description: "Run linters for Go and Flutter"
-        required: true
-        type: boolean
-        default: true
-      run_backend_tests:
-        description: "Run backend Go tests"
-        required: true
-        type: boolean
-        default: true
-      run_userfront_tests:
-        description: "Run userfront Flutter tests"
-        required: true
-        type: boolean
-        default: true
+    pull_request:
+        branches:
+            - dev
+    workflow_dispatch:
+        inputs:
+            run_lint:
+                description: "Run linters for Go and Flutter"
+                required: true
+                type: boolean
+                default: true
+            run_backend_tests:
+                description: "Run backend Go tests"
+                required: true
+                type: boolean
+                default: true
+            run_userfront_tests:
+                description: "Run userfront Flutter tests"
+                required: true
+                type: boolean
+                default: true

 jobs:
-  lint:
-    if: ${{ inputs.run_lint == true }}
-    runs-on: ubuntu-latest
-    steps:
-      - name: Checkout code
-        uses: actions/checkout@v4
+    lint:
+        if: ${{ github.event_name != 'workflow_dispatch' || inputs.run_lint == true }}
+        runs-on: ubuntu-latest
+        steps:
+            - name: Checkout code
+              uses: actions/checkout@v4

-      - name: Setup Node.js
-        uses: actions/setup-node@v4
-        with:
-          node-version: "20"
+            - name: Setup Node.js
+              uses: actions/setup-node@v4
+              with:
+                  node-version: "20"

-      - name: i18n resource check
-        run: |
-          node tools/i18n-scanner/index.js
+            - name: i18n resource check
+              run: |
+                  mkdir -p reports
+                  node tools/i18n-scanner/index.js
+                  node tools/i18n-scanner/report.js
+                  cat reports/i18n-report.txt

-      - name: Setup Go
-        uses: actions/setup-go@v5
-        with:
-          go-version: "1.25"
-          cache-dependency-path: backend/go.sum
+            - name: Setup Go
+              uses: actions/setup-go@v5
+              with:
+                  go-version: "1.25"
+                  cache-dependency-path: backend/go.sum

-      - name: Setup Flutter
-        uses: subosito/flutter-action@v2
-        with:
-          channel: "stable"
-          cache: true
+            - name: Setup Flutter
+              uses: subosito/flutter-action@v2
+              with:
+                  channel: "stable"
+                  cache: true

-      - name: Lint Go backend
-        uses: golangci/golangci-lint-action@v6
-        with:
-          version: v1.59
-          working-directory: backend
-          args: --enable-only=gofmt,gofumpt
+            - name: Lint Go backend
+              uses: golangci/golangci-lint-action@v6
+              with:
+                  version: v1.59
+                  working-directory: backend
+                  args: --enable-only=gofmt,gofumpt

-      - name: Analyze Flutter userfront
-        run: |
-          cd userfront
-          flutter analyze --no-fatal-warnings --no-fatal-infos
+            - name: Analyze Flutter userfront
+              run: |
+                  cd userfront
+                  flutter analyze --no-fatal-warnings --no-fatal-infos

-  backend-tests:
-    needs: lint
-    if: ${{ inputs.run_backend_tests == true }}
-    runs-on: ubuntu-latest
-    services:
-      redis:
-        image: redis:7-alpine
-        options: >
-          --health-cmd "redis-cli ping" --health-interval 10s --health-timeout 5s --health-retries 5
-      clickhouse:
-        image: clickhouse/clickhouse-server:24.6
-        options: >
-          --health-cmd "wget -qO- 'http://localhost:8123/ping'" --health-interval 10s --health-timeout 5s --health-retries 5
+    backend-tests:
+        needs: lint
+        if: ${{ github.event_name != 'workflow_dispatch' || inputs.run_backend_tests == true }}
+        runs-on: ubuntu-latest
+        services:
+            redis:
+                image: redis:7-alpine
+                options: >
+                    --health-cmd "redis-cli ping" --health-interval 10s --health-timeout 5s --health-retries 5
+            clickhouse:
+                image: clickhouse/clickhouse-server:24.6
+                options: >
+                    --health-cmd "wget -qO- 'http://localhost:8123/ping'" --health-interval 10s --health-timeout 5s --health-retries 5

-    env:
-      REDIS_ADDR: redis:6379
-      CLICKHOUSE_HOST: clickhouse
-      CLICKHOUSE_PORT_NATIVE: 9000
+        env:
+            REDIS_ADDR: redis:6379
+            CLICKHOUSE_HOST: clickhouse
+            CLICKHOUSE_PORT_NATIVE: 9000

-    steps:
-      - name: Checkout code
-        uses: actions/checkout@v4
+        steps:
+            - name: Checkout code
+              uses: actions/checkout@v4

-      - name: Setup Go
-        uses: actions/setup-go@v5
-        with:
-          go-version: "1.25"
-          cache-dependency-path: backend/go.sum
+            - name: Setup Go
+              uses: actions/setup-go@v5
+              with:
+                  go-version: "1.25"
+                  cache-dependency-path: backend/go.sum

-      - name: Run backend tests
-        run: |
-          cd backend
-          go test -v ./...
+            - name: Run backend tests
+              run: |
+                  cd backend
+                  go test -v ./...

-  userfront-tests:
-    needs: lint
-    if: ${{ inputs.run_userfront_tests == true }}
-    runs-on: ubuntu-latest
-    steps:
-      - name: Checkout code
-        uses: actions/checkout@v4
+    userfront-tests:
+        needs: lint
+        if: ${{ github.event_name != 'workflow_dispatch' || inputs.run_userfront_tests == true }}
+        runs-on: ubuntu-latest
+        steps:
+            - name: Checkout code
+              uses: actions/checkout@v4

-      - name: Setup Flutter
-        uses: subosito/flutter-action@v2
-        with:
-          channel: "stable"
-          cache: true
+            - name: Setup Flutter
+              uses: subosito/flutter-action@v2
+              with:
+                  channel: "stable"
+                  cache: true

-      - name: Run userfront tests
-        run: |
-          cd userfront
-          if [ -d test ]; then
-            flutter test
-          else
-            echo "No userfront tests: skipping (test/ directory not found)."
-          fi
+            - name: Run userfront tests
+              run: |
+                  cd userfront
+                  if [ -d test ]; then
+                    flutter test
+                    flutter test --platform chrome test/locale_storage_web_test.dart
+                  else
+                    echo "No userfront tests: skipping (test/ directory not found)."
+                  fi
--- a/README.md
+++ b/README.md
@@ -55,7 +55,7 @@ flowchart
  - userfront가 바라보는 backend

 ### 2. UserFront(Flutter Web/App)
- **Framework**: Flutter 3.32+
+- **Framework**: Flutter 3.38.0+
 - **Key Packages**: `flutter_riverpod`, `go_router`
 - **Features**:
  - 탭 기반 로그인 UI (비밀번호 기반 / 링크 기반 / QR 기반 등)
@@ -147,7 +147,7 @@ Kratos가 사용자 SoT이며 Hydra는 순수 OIDC 토큰 엔진입니다. 비

 ### 사전 요구사항 (Prerequisites)
 - Docker & Docker Compose
- Flutter SDK (로컬 개발용)
+- Flutter SDK (로컬 개발용, 3.38.0+)
 - Go (로컬 백엔드 개발용)

 ### 환경 설정 (Environment Setup)
--- a/README_en.md
+++ b/README_en.md
@@ -6,7 +6,7 @@ It leverages **Descope** for secure, passwordless authentication (Enchanted Link
 ## 🏗 Architecture

 ### 1. Frontend (Flutter Web)
- **Framework**: Flutter 3.32+
+- **Framework**: Flutter 3.38.0+
 - **Organization**: `kr.co.baroncs`
 - **Key Packages**: `descope`, `flutter_riverpod`, `go_router`
 - **Features**:
@@ -32,7 +32,7 @@ It leverages **Descope** for secure, passwordless authentication (Enchanted Link

 ### Prerequisites
 - Docker & Docker Compose
- Flutter SDK (for local development)
+- Flutter SDK (for local development, 3.38.0+)
 - Go (for local backend development)

 ### Environment Setup
--- a/adminfront/src/components/common/LanguageSelector.tsx
+++ b/adminfront/src/components/common/LanguageSelector.tsx
@@ -0,0 +1,57 @@
+import { useState } from "react";
+import { t } from "../../lib/i18n";
+
+const LOCALE_STORAGE_KEY = "locale";
+const SUPPORTED_LOCALES = ["ko", "en"] as const;
+
+type Locale = (typeof SUPPORTED_LOCALES)[number];
+
+function resolveLocale(): Locale {
+  if (typeof window === "undefined") {
+    return "ko";
+  }
+
+  const stored = window.localStorage.getItem(LOCALE_STORAGE_KEY);
+  if (stored === "ko" || stored === "en") {
+    return stored;
+  }
+
+  const pathLocale = window.location.pathname.split("/")[1];
+  if (pathLocale === "ko" || pathLocale === "en") {
+    return pathLocale;
+  }
+
+  const browserLang = window.navigator.language.toLowerCase();
+  return browserLang.startsWith("ko") ? "ko" : "en";
+}
+
+function LanguageSelector() {
+  const [locale, setLocale] = useState<Locale>(resolveLocale());
+
+  const handleChange = (next: Locale) => {
+    if (next === locale) {
+      return;
+    }
+    window.localStorage.setItem(LOCALE_STORAGE_KEY, next);
+    setLocale(next);
+    window.location.reload();
+  };
+
+  return (
+    <select
+      value={locale}
+      onChange={(event) => handleChange(event.target.value as Locale)}
+      className="rounded-full border border-border bg-transparent px-3 py-2 text-sm text-muted-foreground transition hover:bg-muted/20"
+      aria-label={t("ui.common.language", "언어")}
+    >
+      <option value="ko">
+        {t("ui.common.language_ko", "한국어")}
+      </option>
+      <option value="en">
+        {t("ui.common.language_en", "English")}
+      </option>
+    </select>
+  );
+}
+
+export default LanguageSelector;
--- a/adminfront/src/components/layout/AppLayout.tsx
+++ b/adminfront/src/components/layout/AppLayout.tsx
@@ -13,6 +13,7 @@ import {
 import { useEffect, useState } from "react";
 import { NavLink, Outlet } from "react-router-dom";
 import { t } from "../../lib/i18n";
+import LanguageSelector from "../common/LanguageSelector";
 import RoleSwitcher from "./RoleSwitcher";

 const navItems = [
@@ -132,6 +133,7 @@ function AppLayout() {
              </span>
            </div>
            <div className="flex items-center gap-2 text-sm">
+              <LanguageSelector />
              <button
                type="button"
                onClick={toggleTheme}
--- a/backend/internal/handler/auth_handler.go
+++ b/backend/internal/handler/auth_handler.go
@@ -454,7 +454,8 @@ func (h *AuthHandler) Signup(c *fiber.Ctx) error {

 	slog.Info("[Signup] New user registered", "email", req.Email, "type", req.AffiliationType, "provider", h.IdpProvider.Name(), "subject", providerID)

-	// [New] Local DB Sync
+	// [SoT Policy] Kratos가 SoT이므로 로컬 DB 저장은 비동기 Read-Model 동기화로 처리합니다.
+	// 로컬 DB 저장이 실패하더라도 회원가입 프로세스는 성공으로 간주합니다.
 	localUser := &domain.User{
 		ID:              providerID, // Match IDP Subject
 		Email:           req.Email,
@@ -470,9 +471,17 @@ func (h *AuthHandler) Signup(c *fiber.Ctx) error {
 	}

 	if h.UserRepo != nil {
-		if err := h.UserRepo.Create(c.Context(), localUser); err != nil {
-			slog.Error("[Signup] Failed to sync user to local DB", "email", req.Email, "error", err)
-		}
+		go func(u *domain.User) {
+			// 요청 Context가 취소될 수 있으므로 Background Context 사용
+			ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+			defer cancel()
+
+			if err := h.UserRepo.Create(ctx, u); err != nil {
+				slog.Error("[Signup] Failed to sync user to Read-Model (Local DB)", "email", u.Email, "error", err)
+			} else {
+				slog.Debug("[Signup] Synced user to Read-Model", "email", u.Email)
+			}
+		}(localUser)
 	}

 	// [Keto] Sync user-tenant relationship
--- a/backend/internal/handler/auth_handler_async_test.go
+++ b/backend/internal/handler/auth_handler_async_test.go
@@ -0,0 +1,251 @@
+package handler
+
+import (
+	"baron-sso-backend/internal/domain"
+	"baron-sso-backend/internal/service"
+	"bytes"
+	"context"
+	"encoding/json"
+	"errors"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+	"time"
+
+	"github.com/gofiber/fiber/v2"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/mock"
+)
+
+// --- Async Test Mocks ---
+
+type AsyncMockIdpProvider struct {
+	mock.Mock
+}
+
+func (m *AsyncMockIdpProvider) Name() string { return "mock-idp" }
+func (m *AsyncMockIdpProvider) GetMetadata() (*domain.IDPMetadata, error) {
+	return &domain.IDPMetadata{}, nil
+}
+func (m *AsyncMockIdpProvider) UserExists(loginID string) (bool, error) {
+	args := m.Called(loginID)
+	return args.Bool(0), args.Error(1)
+}
+func (m *AsyncMockIdpProvider) CreateUser(user *domain.BrokerUser, password string) (string, error) {
+	args := m.Called(user, password)
+	return args.String(0), args.Error(1)
+}
+func (m *AsyncMockIdpProvider) SignIn(loginID, password string) (*domain.AuthInfo, error) {
+	return nil, nil
+}
+func (m *AsyncMockIdpProvider) IssueSession(loginID string) (*domain.AuthInfo, error) { return nil, nil }
+func (m *AsyncMockIdpProvider) InitiateLinkLogin(loginID, returnTo string) (*domain.LinkLoginInit, error) {
+	return nil, nil
+}
+func (m *AsyncMockIdpProvider) VerifyLoginCode(loginID, flowID, code string) (*domain.AuthInfo, error) {
+	return nil, nil
+}
+func (m *AsyncMockIdpProvider) GetPasswordPolicy() (*domain.PasswordPolicy, error) {
+	return &domain.PasswordPolicy{MinLength: 12}, nil
+}
+func (m *AsyncMockIdpProvider) InitiatePasswordReset(loginID, redirectUrl string) error { return nil }
+func (m *AsyncMockIdpProvider) VerifyPasswordResetToken(token string) (*domain.AuthInfo, error) {
+	return nil, nil
+}
+func (m *AsyncMockIdpProvider) UpdateUserPassword(loginID, newPassword string, r *http.Request) error {
+	return nil
+}
+
+type AsyncMockUserRepo struct {
+	mock.Mock
+	createCalled chan bool
+}
+
+func (m *AsyncMockUserRepo) Create(ctx context.Context, user *domain.User) error {
+	// Simulate DB latency
+	time.Sleep(50 * time.Millisecond)
+	args := m.Called(ctx, user)
+	if m.createCalled != nil {
+		m.createCalled <- true
+	}
+	return args.Error(0)
+}
+func (m *AsyncMockUserRepo) Update(ctx context.Context, user *domain.User) error { return nil }
+func (m *AsyncMockUserRepo) FindByEmail(ctx context.Context, email string) (*domain.User, error) {
+	return nil, nil
+}
+func (m *AsyncMockUserRepo) FindByID(ctx context.Context, id string) (*domain.User, error) {
+	return nil, nil
+}
+func (m *AsyncMockUserRepo) FindByIDs(ctx context.Context, ids []string) ([]domain.User, error) {
+	return nil, nil
+}
+func (m *AsyncMockUserRepo) ListByTenant(ctx context.Context, tenantID string) ([]domain.User, error) {
+	return nil, nil
+}
+func (m *AsyncMockUserRepo) List(ctx context.Context, offset, limit int, search string) ([]domain.User, int64, error) {
+	return nil, 0, nil
+}
+
+type AsyncMockRedisRepo struct {
+	mock.Mock
+}
+
+func (m *AsyncMockRedisRepo) Set(key string, value string, expiration time.Duration) error {
+	args := m.Called(key, value, expiration)
+	return args.Error(0)
+}
+func (m *AsyncMockRedisRepo) Get(key string) (string, error) {
+	args := m.Called(key)
+	return args.String(0), args.Error(1)
+}
+func (m *AsyncMockRedisRepo) Delete(key string) error {
+	args := m.Called(key)
+	return args.Error(0)
+}
+func (m *AsyncMockRedisRepo) StoreVerificationCode(phone, code string) error   { return nil }
+func (m *AsyncMockRedisRepo) GetVerificationCode(phone string) (string, error) { return "", nil }
+func (m *AsyncMockRedisRepo) DeleteVerificationCode(phone string) error        { return nil }
+
+type AsyncMockTenantService struct {
+	mock.Mock
+}
+
+func (m *AsyncMockTenantService) RegisterTenant(ctx context.Context, name, slug, description string, domains []string) (*domain.Tenant, error) {
+	return nil, nil
+}
+func (m *AsyncMockTenantService) RequestRegistration(ctx context.Context, name, slug, description string, domainName string, adminEmail string) (*domain.Tenant, error) {
+	return nil, nil
+}
+func (m *AsyncMockTenantService) GetTenantByDomain(ctx context.Context, emailDomain string) (*domain.Tenant, error) {
+	args := m.Called(ctx, emailDomain)
+	if args.Get(0) == nil {
+		return nil, args.Error(1)
+	}
+	return args.Get(0).(*domain.Tenant), args.Error(1)
+}
+func (m *AsyncMockTenantService) GetTenantBySlug(ctx context.Context, slug string) (*domain.Tenant, error) {
+	return nil, nil
+}
+func (m *AsyncMockTenantService) GetTenant(ctx context.Context, id string) (*domain.Tenant, error) {
+	return nil, nil
+}
+func (m *AsyncMockTenantService) ListManageableTenants(ctx context.Context, userID string) ([]domain.Tenant, error) {
+	return nil, nil
+}
+func (m *AsyncMockTenantService) ApproveTenant(ctx context.Context, id string) error { return nil }
+func (m *AsyncMockTenantService) SetKetoService(keto service.KetoService)           {}
+func (m *AsyncMockTenantService) AddTenantAdmin(ctx context.Context, tenantID, userID string) error {
+	return nil
+}
+func (m *AsyncMockTenantService) RemoveTenantAdmin(ctx context.Context, tenantID, userID string) error {
+	return nil
+}
+func (m *AsyncMockTenantService) ListTenantAdmins(ctx context.Context, tenantID string) ([]string, error) {
+	return nil, nil
+}
+
+type AsyncMockKetoService struct {
+	mock.Mock
+}
+
+func (m *AsyncMockKetoService) CreateRelation(ctx context.Context, namespace, object, relation, subject string) error {
+	args := m.Called(ctx, namespace, object, relation, subject)
+	return args.Error(0)
+}
+func (m *AsyncMockKetoService) DeleteRelation(ctx context.Context, namespace, object, relation, subject string) error {
+	return nil
+}
+func (m *AsyncMockKetoService) CheckPermission(ctx context.Context, namespace, object, relation, subject string) (bool, error) {
+	return false, nil
+}
+func (m *AsyncMockKetoService) ListObjects(ctx context.Context, namespace, relation, subject string) ([]string, error) {
+	return nil, nil
+}
+func (m *AsyncMockKetoService) ListRelations(ctx context.Context, namespace, object, relation, subject string) ([]service.RelationTuple, error) {
+	return nil, nil
+}
+
+// --- Tests ---
+
+func TestSignup_AsyncDB_Isolation(t *testing.T) {
+	mockIdp := new(AsyncMockIdpProvider)
+	mockUserRepo := new(AsyncMockUserRepo)
+	mockRedis := new(AsyncMockRedisRepo)
+	mockTenant := new(AsyncMockTenantService)
+	mockKeto := new(AsyncMockKetoService)
+
+	h := &AuthHandler{
+		IdpProvider:   mockIdp,
+		UserRepo:      mockUserRepo,
+		RedisService:  mockRedis,
+		TenantService: mockTenant,
+		KetoService:   mockKeto,
+	}
+
+	app := fiber.New()
+	app.Post("/signup", h.Signup)
+
+	t.Run("SoT_DB_Failure_Ignored_And_Async", func(t *testing.T) {
+		email := "test@example.com"
+		phone := "010-1234-5678"
+		emailKey := "signup:email:" + email
+		phoneKey := "signup:phone:" + "01012345678"
+
+		// Redis Mocks
+		mockRedis.On("Get", emailKey).Return(`{"verified": true, "expires_at": 9999999999}`, nil)
+		mockRedis.On("Get", phoneKey).Return(`{"verified": true, "expires_at": 9999999999}`, nil)
+		mockRedis.On("Delete", emailKey).Return(nil)
+		mockRedis.On("Delete", phoneKey).Return(nil)
+
+		// Tenant Mocks
+		mockTenant.On("GetTenantByDomain", mock.Anything, "example.com").Return(nil, errors.New("not found"))
+
+		// Kratos Mocks (Success)
+		mockIdp.On("CreateUser", mock.Anything, "Password123!").Return("new-user-uuid", nil)
+
+		// UserRepo Mocks (Async & Failure)
+		mockUserRepo.createCalled = make(chan bool, 1)
+		mockUserRepo.On("Create", mock.Anything, mock.MatchedBy(func(u *domain.User) bool {
+			return u.Email == email
+		})).Return(errors.New("db connection error"))
+
+		// Keto Mocks (Optional, since it's also async)
+		// We won't block on this either
+
+		body, _ := json.Marshal(domain.SignupRequest{
+			Email:         email,
+			Password:      "Password123!",
+			Name:          "Test User",
+			Phone:         phone,
+			TermsAccepted: true,
+		})
+		req := httptest.NewRequest("POST", "/signup", bytes.NewReader(body))
+		req.Header.Set("Content-Type", "application/json")
+
+		start := time.Now()
+		resp, err := app.Test(req, 5000)
+		elapsed := time.Since(start)
+
+		if err != nil {
+			t.Fatalf("Request failed: %v", err)
+		}
+
+		assert.Equal(t, 200, resp.StatusCode)
+
+		// Ensure API responded faster than DB latency (50ms)
+		assert.Less(t, int64(elapsed), int64(60*time.Millisecond), "API should return before DB timeout")
+
+		// Wait for async execution
+		select {
+		case <-mockUserRepo.createCalled:
+			// Pass
+		case <-time.After(2 * time.Second):
+			t.Fatal("UserRepo.Create was not called asynchronously")
+		}
+
+		mockRedis.AssertExpectations(t)
+		mockIdp.AssertExpectations(t)
+		mockUserRepo.AssertExpectations(t)
+	})
+}
--- a/backend/internal/handler/user_handler.go
+++ b/backend/internal/handler/user_handler.go
@@ -304,10 +304,15 @@ func (h *UserHandler) CreateUser(c *fiber.Ctx) error {
 		localUser.TenantID = &tenantID
 	}

+	// [SoT Policy] Kratos가 SoT이므로 로컬 DB 저장은 비동기 Read-Model 동기화로 처리합니다.
 	if h.UserRepo != nil {
-		if err := h.UserRepo.Create(c.Context(), localUser); err != nil {
-			slog.Error("[UserHandler] Failed to sync user to local DB", "email", email, "error", err)
-		}
+		go func(u *domain.User) {
+			ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+			defer cancel()
+			if err := h.UserRepo.Create(ctx, u); err != nil {
+				slog.Error("[UserHandler] Failed to sync user to local DB", "email", u.Email, "error", err)
+			}
+		}(localUser)
 	}

 	// [Keto] Sync relations
@@ -483,27 +488,32 @@ func (h *UserHandler) UpdateUser(c *fiber.Ctx) error {
 				localUser.Metadata = req.Metadata
 			}

-			if err := h.UserRepo.Update(c.Context(), localUser); err == nil {
-				// [Keto Sync on Role Change]
-				if h.KetoService != nil && req.Role != nil && *req.Role != oldRole {
-					go func(uID, oldR, newR, tID string) {
-						ctx := context.Background()
-						if oldR == domain.RoleSuperAdmin {
+			// [SoT Policy] Kratos가 SoT이므로 로컬 DB 저장은 비동기 Read-Model 동기화로 처리합니다.
+			go func(u *domain.User, rRole *string, oRole string, oTenantID string) {
+				ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+				defer cancel()
+
+				if err := h.UserRepo.Update(ctx, u); err == nil {
+					// [Keto Sync on Role Change]
+					if h.KetoService != nil && rRole != nil && *rRole != oRole {
+						uID := u.ID
+						newR := *rRole
+						if oRole == domain.RoleSuperAdmin {
 							_ = h.KetoService.DeleteRelation(ctx, "System", "global", "super_admins", uID)
-						} else if oldR == domain.RoleTenantAdmin && tID != "" {
-							_ = h.KetoService.DeleteRelation(ctx, "Tenant", tID, "admins", uID)
+						} else if oRole == domain.RoleTenantAdmin && oTenantID != "" {
+							_ = h.KetoService.DeleteRelation(ctx, "Tenant", oTenantID, "admins", uID)
 						}

 						if newR == domain.RoleSuperAdmin {
 							_ = h.KetoService.CreateRelation(ctx, "System", "global", "super_admins", uID)
-						} else if newR == domain.RoleTenantAdmin && tID != "" {
-							_ = h.KetoService.CreateRelation(ctx, "Tenant", tID, "admins", uID)
+						} else if newR == domain.RoleTenantAdmin && u.TenantID != nil {
+							_ = h.KetoService.CreateRelation(ctx, "Tenant", *u.TenantID, "admins", uID)
 						}
-					}(userID, oldRole, *req.Role, oldTenantID)
+					}
+				} else {
+					slog.Error("[UserHandler] Failed to sync user update to local DB", "userID", u.ID, "error", err)
 				}
-			} else {
-				slog.Error("[UserHandler] Failed to sync user update to local DB", "userID", userID, "error", err)
-			}
+			}(localUser, req.Role, oldRole, oldTenantID)
 		}
 	}

--- a/devfront/src/components/common/LanguageSelector.tsx
+++ b/devfront/src/components/common/LanguageSelector.tsx
@@ -0,0 +1,57 @@
+import { useState } from "react";
+import { t } from "../../lib/i18n";
+
+const LOCALE_STORAGE_KEY = "locale";
+const SUPPORTED_LOCALES = ["ko", "en"] as const;
+
+type Locale = (typeof SUPPORTED_LOCALES)[number];
+
+function resolveLocale(): Locale {
+  if (typeof window === "undefined") {
+    return "ko";
+  }
+
+  const stored = window.localStorage.getItem(LOCALE_STORAGE_KEY);
+  if (stored === "ko" || stored === "en") {
+    return stored;
+  }
+
+  const pathLocale = window.location.pathname.split("/")[1];
+  if (pathLocale === "ko" || pathLocale === "en") {
+    return pathLocale;
+  }
+
+  const browserLang = window.navigator.language.toLowerCase();
+  return browserLang.startsWith("ko") ? "ko" : "en";
+}
+
+function LanguageSelector() {
+  const [locale, setLocale] = useState<Locale>(resolveLocale());
+
+  const handleChange = (next: Locale) => {
+    if (next === locale) {
+      return;
+    }
+    window.localStorage.setItem(LOCALE_STORAGE_KEY, next);
+    setLocale(next);
+    window.location.reload();
+  };
+
+  return (
+    <select
+      value={locale}
+      onChange={(event) => handleChange(event.target.value as Locale)}
+      className="rounded-full border border-border bg-transparent px-3 py-2 text-sm text-muted-foreground transition hover:bg-muted/20"
+      aria-label={t("ui.common.language", "언어")}
+    >
+      <option value="ko">
+        {t("ui.common.language_ko", "한국어")}
+      </option>
+      <option value="en">
+        {t("ui.common.language_en", "English")}
+      </option>
+    </select>
+  );
+}
+
+export default LanguageSelector;
--- a/devfront/src/components/layout/AppLayout.tsx
+++ b/devfront/src/components/layout/AppLayout.tsx
@@ -2,6 +2,7 @@ import { BadgeCheck, Moon, ShieldHalf, Sun } from "lucide-react";
 import { useEffect, useState } from "react";
 import { NavLink, Outlet } from "react-router-dom";
 import { t } from "../../lib/i18n";
+import LanguageSelector from "../common/LanguageSelector";
 import { Toaster } from "../ui/toaster";

 const navItems = [
@@ -105,6 +106,7 @@ function AppLayout() {
              </span>
            </div>
            <div className="flex items-center gap-2 text-sm">
+              <LanguageSelector />
              <button
                type="button"
                onClick={toggleTheme}
--- a/docker-compose.yaml
+++ b/docker-compose.yaml
@@ -11,8 +11,8 @@ services:
            - GO_ENV=${APP_ENV:-development}
            - COOKIE_SECRET=${COOKIE_SECRET}
            - JWT_SECRET=${JWT_SECRET}
-            - DESCOPE_PROJECT_ID=${DESCOPE_PROJECT_ID}
-            - DESCOPE_MANAGEMENT_KEY=${DESCOPE_MANAGEMENT_KEY}
+            - DESCOPE_PROJECT_ID=${DESCOPE_PROJECT_ID:-}
+            - DESCOPE_MANAGEMENT_KEY=${DESCOPE_MANAGEMENT_KEY:-}
            - NAVER_CLOUD_ACCESS_KEY=${NAVER_CLOUD_ACCESS_KEY}
            - NAVER_CLOUD_SECRET_KEY=${NAVER_CLOUD_SECRET_KEY}
            - NAVER_CLOUD_SERVICE_ID=${NAVER_CLOUD_SERVICE_ID}
@@ -82,13 +82,13 @@ services:

    userfront:
        build:
-            context: ./userfront
-            dockerfile: Dockerfile
+            context: .
+            dockerfile: userfront/Dockerfile
        container_name: baron_userfront
        env_file:
            - .env
        environment:
-            - BACKEND_URL=${BACKEND_URL}
+            - BACKEND_URL=${BACKEND_URL:-}
            - USERFRONT_URL=${USERFRONT_URL}
            - APP_ENV=${APP_ENV}
        networks:
--- a/docker/compose.ory.yaml
+++ b/docker/compose.ory.yaml
@@ -1,135 +1,136 @@
 services:
-  postgres_ory:
-    image: postgres:${ORY_POSTGRES_TAG:-17-alpine}
-    container_name: ory_postgres
-    environment:
-      - POSTGRES_USER=${ORY_POSTGRES_USER:-ory}
-      - POSTGRES_PASSWORD=${ORY_POSTGRES_PASSWORD:-secret}
-      - POSTGRES_DB=${ORY_POSTGRES_DB:-ory}
-    volumes:
-      - ./docker/ory/init-db:/docker-entrypoint-initdb.d
-      - ory_postgres_data:/var/lib/postgresql/data
-    networks:
-      - ory-net
-    healthcheck:
-      test:
-        [
-          "CMD-SHELL",
-          "pg_isready -U ${ORY_POSTGRES_USER:-ory} -d ${KRATOS_DB:-ory_kratos}",
-        ]
-      interval: 5s
-      timeout: 5s
-      retries: 5
+    postgres_ory:
+        image: postgres:${ORY_POSTGRES_TAG:-17-alpine}
+        container_name: ory_postgres
+        environment:
+            - POSTGRES_USER=${ORY_POSTGRES_USER:-ory}
+            - POSTGRES_PASSWORD=${ORY_POSTGRES_PASSWORD:-secret}
+            - POSTGRES_DB=${ORY_POSTGRES_DB:-ory}
+        volumes:
+            - ./docker/ory/init-db:/docker-entrypoint-initdb.d
+            - ory_postgres_data:/var/lib/postgresql/data
+        networks:
+            - ory-net
+        healthcheck:
+            test:
+                [
+                    "CMD-SHELL",
+                    "pg_isready -U ${ORY_POSTGRES_USER:-ory} -d ${KRATOS_DB:-ory_kratos}",
+                ]
+            interval: 5s
+            timeout: 5s
+            retries: 5

-  kratos-migrate:
-    image: oryd/kratos:${KRATOS_VERSION:-v25.4.0}
-    environment:
-      - DSN=postgres://${ORY_POSTGRES_USER}:${ORY_POSTGRES_PASSWORD}@postgres_ory:5432/${KRATOS_DB:-ory_kratos}?sslmode=disable&max_conns=20
-      - KRATOS_SERVE_PUBLIC_BASE_URL="${KRATOS_BROWSER_URL:-http://localhost:4433}"
-      - KRATOS_SERVE_ADMIN_BASE_URL="${KRATOS_ADMIN_URL:-http://kratos:4434}"
-      - KRATOS_SELFSERVICE_DEFAULT_BROWSER_RETURN_URL="${KRATOS_UI_URL:-http://localhost:5000}"
-      - KRATOS_SELFSERVICE_ALLOWED_RETURN_URLS='["${KRATOS_UI_URL:-http://localhost:5000}","${USERFRONT_URL:-http://localhost:5000}"]'
-    volumes:
-      - ./docker/ory/kratos:/etc/config/kratos
-    command: migrate sql up -e -c /etc/config/kratos/kratos.yml --yes
-    depends_on:
-      postgres_ory:
-        condition: service_healthy
-    networks:
-      - ory-net
+    kratos-migrate:
+        image: oryd/kratos:${KRATOS_VERSION:-v25.4.0}
+        environment:
+            - DSN=postgres://${ORY_POSTGRES_USER}:${ORY_POSTGRES_PASSWORD}@postgres_ory:5432/${KRATOS_DB:-ory_kratos}?sslmode=disable&max_conns=20
+            - KRATOS_SERVE_PUBLIC_BASE_URL="${KRATOS_BROWSER_URL:-http://localhost:4433}"
+            - KRATOS_SERVE_ADMIN_BASE_URL="${KRATOS_ADMIN_URL:-http://kratos:4434}"
+            - KRATOS_SELFSERVICE_DEFAULT_BROWSER_RETURN_URL="${KRATOS_UI_URL:-http://localhost:5000}"
+            - KRATOS_SELFSERVICE_ALLOWED_RETURN_URLS='["${KRATOS_UI_URL:-http://localhost:5000}","${USERFRONT_URL:-http://localhost:5000}"]'
+        volumes:
+            - ./docker/ory/kratos:/etc/config/kratos
+        command: migrate sql up -e -c /etc/config/kratos/kratos.yml --yes
+        depends_on:
+            postgres_ory:
+                condition: service_healthy
+        networks:
+            - ory-net

-  kratos:
-    image: oryd/kratos:${KRATOS_VERSION:-v25.4.0}
-    container_name: ory_kratos
-    environment:
-      - DSN=postgres://${ORY_POSTGRES_USER}:${ORY_POSTGRES_PASSWORD}@postgres_ory:5432/${KRATOS_DB:-ory_kratos}?sslmode=disable&max_conns=20
-      - COOKIE_SECRET="${COOKIE_SECRET:-localcookie123}"
-      - KRATOS_SERVE_PUBLIC_BASE_URL="${KRATOS_BROWSER_URL:-http://localhost:4433}"
-      - KRATOS_SERVE_ADMIN_BASE_URL="${KRATOS_ADMIN_URL:-http://kratos:4434}"
-      - KRATOS_SELFSERVICE_DEFAULT_BROWSER_RETURN_URL="${KRATOS_UI_URL:-http://localhost:5000}"
-      - KRATOS_SELFSERVICE_ALLOWED_RETURN_URLS='["${KRATOS_UI_URL:-http://localhost:5000}","${USERFRONT_URL:-http://localhost:5000}"]'
-    volumes:
-      - ./docker/ory/kratos:/etc/config/kratos
-    command: serve -c /etc/config/kratos/kratos.yml
-    depends_on:
-      kratos-migrate:
-        condition: service_completed_successfully
-    networks:
-      - ory-net
-      - kratosnet
+    kratos:
+        image: oryd/kratos:${KRATOS_VERSION:-v25.4.0}
+        container_name: ory_kratos
+        environment:
+            - DSN=postgres://${ORY_POSTGRES_USER}:${ORY_POSTGRES_PASSWORD}@postgres_ory:5432/${KRATOS_DB:-ory_kratos}?sslmode=disable&max_conns=20
+            - COOKIE_SECRET="${COOKIE_SECRET:-localcookie123}"
+            - KRATOS_SERVE_PUBLIC_BASE_URL="${KRATOS_BROWSER_URL:-http://localhost:4433}"
+            - KRATOS_SERVE_ADMIN_BASE_URL="${KRATOS_ADMIN_URL:-http://kratos:4434}"
+            - KRATOS_SELFSERVICE_DEFAULT_BROWSER_RETURN_URL="${KRATOS_UI_URL:-http://localhost:5000}"
+            - KRATOS_SELFSERVICE_ALLOWED_RETURN_URLS='["${KRATOS_UI_URL:-http://localhost:5000}","${USERFRONT_URL:-http://localhost:5000}"]'
+        volumes:
+            - ./docker/ory/kratos:/etc/config/kratos
+        command: serve -c /etc/config/kratos/kratos.yml
+        depends_on:
+            kratos-migrate:
+                condition: service_completed_successfully
+        networks:
+            - ory-net
+            - kratosnet

-  hydra-migrate:
-    image: oryd/hydra:${HYDRA_VERSION:-v25.4.0}
-    environment:
-      - DSN=postgres://${ORY_POSTGRES_USER}:${ORY_POSTGRES_PASSWORD}@postgres_ory:5432/${HYDRA_DB:-ory_hydra}?sslmode=disable&max_conns=20
-    command: migrate sql up -e --yes
-    depends_on:
-      postgres_ory:
-        condition: service_healthy
-    networks:
-      - ory-net
+    hydra-migrate:
+        image: oryd/hydra:${HYDRA_VERSION:-v25.4.0}
+        environment:
+            - DSN=postgres://${ORY_POSTGRES_USER}:${ORY_POSTGRES_PASSWORD}@postgres_ory:5432/${HYDRA_DB:-ory_hydra}?sslmode=disable&max_conns=20
+        command: migrate sql up -e --yes
+        depends_on:
+            postgres_ory:
+                condition: service_healthy
+        networks:
+            - ory-net

-  hydra:
-    image: oryd/hydra:${HYDRA_VERSION:-v25.4.0}
-    container_name: ory_hydra
-    environment:
-      - DSN=postgres://${ORY_POSTGRES_USER}:${ORY_POSTGRES_PASSWORD}@postgres_ory:5432/${HYDRA_DB:-ory_hydra}?sslmode=disable&max_conns=20
-      - URLS_SELF_ISSUER=${USERFRONT_URL:-http://localhost:5000}/oidc
-      - URLS_LOGIN=${USERFRONT_URL:-http://localhost:5000}/login
-      - URLS_CONSENT=${USERFRONT_URL:-http://localhost:5000}/consent
-      - SECRETS_SYSTEM=${ORY_POSTGRES_PASSWORD}
-    volumes:
-      - ./docker/ory/hydra:/etc/config/hydra
-    command: serve -c /etc/config/hydra/hydra.yml all --dev
-    depends_on:
-      hydra-migrate:
-        condition: service_completed_successfully
-    networks:
-      - ory-net
-      - hydranet
+    hydra:
+        image: oryd/hydra:${HYDRA_VERSION:-v25.4.0}
+        container_name: ory_hydra
+        environment:
+            - DSN=postgres://${ORY_POSTGRES_USER}:${ORY_POSTGRES_PASSWORD}@postgres_ory:5432/${HYDRA_DB:-ory_hydra}?sslmode=disable&max_conns=20
+            - URLS_SELF_ISSUER=${USERFRONT_URL:-http://localhost:5000}/oidc
+            - URLS_LOGIN=${USERFRONT_URL:-http://localhost:5000}/login
+            - URLS_CONSENT=${USERFRONT_URL:-http://localhost:5000}/consent
+            - SECRETS_SYSTEM=${ORY_POSTGRES_PASSWORD}
+        volumes:
+            - ./docker/ory/hydra:/etc/config/hydra
+        command: serve -c /etc/config/hydra/hydra.yml all --dev
+        depends_on:
+            hydra-migrate:
+                condition: service_completed_successfully
+        networks:
+            - ory-net
+            - hydranet

-  # [수정됨] Oathkeeper 서비스 추가 (Backend 연결 문제 해결)
-  oathkeeper:
-    image: oryd/oathkeeper:${OATHKEEPER_VERSION:-v0.40.6}
-    container_name: oathkeeper
-    restart: unless-stopped
-    depends_on:
-      kratos:
-        condition: service_started
-    environment:
-      - LOG_LEVEL=debug
-    command: serve proxy --config /etc/config/oathkeeper/oathkeeper.yml
-    volumes:
-      - ./docker/ory/oathkeeper:/etc/config/oathkeeper
-    networks:
-      - ory-net
-      - baron_net  # Backend가 통신하기 위해 필수
-      - public_net
-    ports:
-      - "4455:4455" # Proxy
-      - "4456:4456" # API (Backend 헬스체크용)
-    healthcheck:
-      test: ["CMD", "wget", "-qO-", "http://127.0.0.1:4456/health/ready"]
-      interval: 5s
-      timeout: 5s
-      retries: 5
+    # [수정됨] Oathkeeper 서비스 추가 (Backend 연결 문제 해결)
+    oathkeeper:
+        image: oryd/oathkeeper:${OATHKEEPER_VERSION:-v0.40.6}
+        container_name: oathkeeper
+        restart: unless-stopped
+        depends_on:
+            kratos:
+                condition: service_started
+        environment:
+            - LOG_LEVEL=debug
+        command: serve proxy --config /etc/config/oathkeeper/oathkeeper.yml
+        volumes:
+            - ./docker/ory/oathkeeper:/etc/config/oathkeeper
+            - oathkeeper_logs:/var/log/oathkeeper
+        networks:
+            - ory-net
+            - baron_net # Backend가 통신하기 위해 필수
+            - public_net
+        ports:
+            - "4455:4455" # Proxy
+            - "4456:4456" # API (Backend 헬스체크용)
+        healthcheck:
+            test: ["CMD", "wget", "-qO-", "http://127.0.0.1:4456/health/ready"]
+            interval: 5s
+            timeout: 5s
+            retries: 5
 volumes:
-  ory_postgres_data:
+    ory_postgres_data:

 networks:
-  ory-net:
-    external: true
-    name: ory-net
-  hydranet:
-    external: true
-    name: hydranet
-  kratosnet:
-    external: true
-    name: kratosnet
-  public_net:
-    external: true
-    name: public_net
-  # [수정됨] Baron Net 추가 정의 (Oathkeeper 연결용)
-  baron_net:
-    external: true
-    name: baron_net
+    ory-net:
+        external: true
+        name: ory-net
+    hydranet:
+        external: true
+        name: hydranet
+    kratosnet:
+        external: true
+        name: kratosnet
+    public_net:
+        external: true
+        name: public_net
+    # [수정됨] Baron Net 추가 정의 (Oathkeeper 연결용)
+    baron_net:
+        external: true
+        name: baron_net
--- a/docker/docker-compose.staging.template.yaml
+++ b/docker/docker-compose.staging.template.yaml
@@ -64,7 +64,7 @@ services:
    env_file:
      - .env
    environment:
-      - BACKEND_URL=${BACKEND_URL}
+      - BACKEND_URL=${BACKEND_URL:-}
      - USERFRONT_URL=${USERFRONT_URL}
      - APP_ENV=stage
    networks:
@@ -75,7 +75,7 @@ services:
        condition: service_healthy
    command: >
      /bin/sh -c "mkdir -p /usr/share/nginx/html/assets &&
-                  echo \"BACKEND_URL=${BACKEND_URL}\" >> /usr/share/nginx/html/assets/.env &&
+                  echo \"BACKEND_URL=${BACKEND_URL:-}\" >> /usr/share/nginx/html/assets/.env &&
                  echo \"USERFRONT_URL=${USERFRONT_URL}\" >> /usr/share/nginx/html/assets/.env &&
                  echo \"APP_ENV=stage\" >> /usr/share/nginx/html/assets/.env &&
                  cp /usr/share/nginx/html/assets/.env /usr/share/nginx/html/.env &&
--- a/docker/ory/kratos/kratos.yml
+++ b/docker/ory/kratos/kratos.yml
@@ -1,4 +1,4 @@
-version: v1.3.0
+version: v25.4.0

 dsn: ${DSN}

@@ -7,19 +7,26 @@ serve:
        base_url: http://localhost:4433/
        cors:
            enabled: true
+            allowed_origins:
+                - http://backend:3000
+                - http://baron_backend:3000
    admin:
        base_url: http://localhost:4434/

 selfservice:
    default_browser_return_url: http://localhost:5000/
    allowed_return_urls:
+        - http://baron_backend:3000
+        - http://baron_backend:3000/
        - http://localhost:5000
+        - https://app.brsw.kr
+        - https://app.brsw.kr/
        - https://sss.hmac.kr
        - https://sss.hmac.kr/
        - https://sso.hmac.kr
        - https://sso.hmac.kr/
-        - https://app.hmac.kr
-        - https://app.hmac.kr/
+        - https://ssologin.hmac.kr
+        - https://ssologin.hmac.kr/

    methods:
        password:
--- a/docker/ory/oathkeeper/entrypoint.sh
+++ b/docker/ory/oathkeeper/entrypoint.sh
@@ -37,7 +37,11 @@ mkdir -p "$LOG_DIR"
 if ! touch "$LOG_FILE" 2>/dev/null; then
  echo "[oathkeeper] log file not writable: $LOG_FILE"
  ls -ld "$LOG_DIR" || true
-  exit 1
+  LOG_FILE=""
 fi

-exec /bin/sh -c "oathkeeper serve proxy -c /etc/config/oathkeeper/oathkeeper.yml 2>&1 | tee \"$LOG_FILE\""
+if [ -n "$LOG_FILE" ]; then
+  exec /bin/sh -c "oathkeeper serve proxy -c /etc/config/oathkeeper/oathkeeper.yml 2>&1 | tee \"$LOG_FILE\""
+fi
+
+exec /bin/sh -c "oathkeeper serve proxy -c /etc/config/oathkeeper/oathkeeper.yml"
--- a/docker/staging_pull_compose.template.yaml
+++ b/docker/staging_pull_compose.template.yaml
@@ -0,0 +1,400 @@
+services:
+  postgres:
+    image: postgres:17-alpine
+    container_name: baron_postgres
+    environment:
+      POSTGRES_USER: "${DB_USER:-baron}"
+      POSTGRES_PASSWORD: "${DB_PASSWORD:-password}"
+      POSTGRES_DB: "${DB_NAME:-baron_sso}"
+    ports:
+      - "${DB_PORT:-5432}:5432"
+    volumes:
+      - postgres_data:/var/lib/postgresql/data
+      - ./docker/init-metadata:/docker-entrypoint-initdb.d
+    networks:
+      - baron_net
+    healthcheck:
+      test:
+        [
+          "CMD-SHELL",
+          "pg_isready -U ${DB_USER:-baron} -d ${DB_NAME:-baron_sso}",
+        ]
+      interval: 5s
+      timeout: 5s
+      retries: 5
+    restart: always
+
+  clickhouse:
+    image: clickhouse/clickhouse-server:latest
+    container_name: baron_clickhouse
+    restart: always
+    volumes:
+      - clickhouse_data:/var/lib/clickhouse
+    environment:
+      CLICKHOUSE_USER: "${CLICKHOUSE_USER:-baron}"
+      CLICKHOUSE_PASSWORD: "${CLICKHOUSE_PASSWORD:-password}"
+    networks:
+      - baron_net
+    healthcheck:
+      test: ["CMD", "clickhouse-client", "--query", "SELECT 1"]
+      interval: 5s
+      timeout: 5s
+      retries: 5
+
+  redis:
+    image: redis:7-alpine
+    container_name: baron_redis
+    restart: always
+    command: redis-server --port 6389
+    ports:
+      - "6389:6389"
+    volumes:
+      - redis_data:/data
+    networks:
+      - baron_net
+    healthcheck:
+      test: ["CMD", "redis-cli", "-p", "6389", "ping"]
+      interval: 5s
+      timeout: 5s
+      retries: 5
+
+  gateway:
+    image: nginx:alpine
+    container_name: baron_gateway
+    restart: always
+    ports:
+      - "${USERFRONT_PORT:-5000}:5000"
+    volumes:
+      - ./gateway/nginx.conf:/etc/nginx/conf.d/default.conf:ro
+    networks:
+      - baron_net
+      - public_net
+    healthcheck:
+      test: ["CMD", "wget", "-qO-", "http://127.0.0.1:5000/"]
+      interval: 10s
+      timeout: 5s
+      retries: 3
+      start_period: 10s
+
+  postgres_ory:
+    image: postgres:${ORY_POSTGRES_TAG:-17-alpine}
+    container_name: ory_postgres
+    environment:
+      - POSTGRES_USER=${ORY_POSTGRES_USER:-ory}
+      - POSTGRES_PASSWORD=${ORY_POSTGRES_PASSWORD:-secret}
+      - POSTGRES_DB=${ORY_POSTGRES_DB:-ory}
+    volumes:
+      - ./docker/ory/init-db:/docker-entrypoint-initdb.d
+      - ory_postgres_data:/var/lib/postgresql/data
+    networks:
+      - ory-net
+    healthcheck:
+      test:
+        [
+          "CMD-SHELL",
+          "pg_isready -U ${ORY_POSTGRES_USER:-ory} -d ${KRATOS_DB:-ory_kratos}",
+        ]
+      interval: 5s
+      timeout: 5s
+      retries: 5
+
+  kratos-migrate:
+    image: oryd/kratos:${KRATOS_VERSION:-v25.4.0}
+    environment:
+      - DSN=postgres://${ORY_POSTGRES_USER}:${ORY_POSTGRES_PASSWORD}@postgres_ory:5432/${KRATOS_DB:-ory_kratos}?sslmode=disable&max_conns=20
+      - KRATOS_SERVE_PUBLIC_BASE_URL=${KRATOS_BROWSER_URL:-http://localhost:4433}
+      - KRATOS_SERVE_ADMIN_BASE_URL=${KRATOS_ADMIN_URL:-http://kratos:4434}
+      - KRATOS_SELFSERVICE_DEFAULT_BROWSER_RETURN_URL=${KRATOS_UI_URL:-http://localhost:5000}
+      - KRATOS_SELFSERVICE_ALLOWED_RETURN_URLS=["${KRATOS_UI_URL:-http://localhost:5000}","${USERFRONT_URL:-http://localhost:5000}"]
+      - KRATOS_SELFSERVICE_FLOWS_ERROR_UI_URL=${KRATOS_UI_URL:-http://localhost:5000}/error
+      - KRATOS_SELFSERVICE_FLOWS_SETTINGS_UI_URL=${KRATOS_UI_URL:-http://localhost:5000}/error?error=settings_disabled
+      - KRATOS_SELFSERVICE_FLOWS_RECOVERY_UI_URL=${KRATOS_UI_URL:-http://localhost:5000}/recovery
+      - KRATOS_SELFSERVICE_FLOWS_VERIFICATION_UI_URL=${KRATOS_UI_URL:-http://localhost:5000}/verification
+      - KRATOS_SELFSERVICE_FLOWS_LOGIN_UI_URL=${KRATOS_UI_URL:-http://localhost:5000}/login
+      - KRATOS_SELFSERVICE_FLOWS_REGISTRATION_UI_URL=${KRATOS_UI_URL:-http://localhost:5000}/registration
+      - KRATOS_SELFSERVICE_FLOWS_LOGOUT_AFTER_DEFAULT_BROWSER_RETURN_URL=${KRATOS_UI_URL:-http://localhost:5000}/login
+    volumes:
+      - ./docker/ory/kratos:/etc/config/kratos
+    command: migrate sql up -e -c /etc/config/kratos/kratos.yml --yes
+    depends_on:
+      postgres_ory:
+        condition: service_healthy
+    networks:
+      - ory-net
+
+  kratos:
+    image: oryd/kratos:${KRATOS_VERSION:-v25.4.0}
+    container_name: ory_kratos
+    environment:
+      - DSN=postgres://${ORY_POSTGRES_USER}:${ORY_POSTGRES_PASSWORD}@postgres_ory:5432/${KRATOS_DB:-ory_kratos}?sslmode=disable&max_conns=20
+      - COOKIE_SECRET=${COOKIE_SECRET:-localcookie123}
+      - KRATOS_SERVE_PUBLIC_BASE_URL=${KRATOS_BROWSER_URL:-http://localhost:4433}
+      - KRATOS_SERVE_ADMIN_BASE_URL=${KRATOS_ADMIN_URL:-http://kratos:4434}
+      - KRATOS_SELFSERVICE_DEFAULT_BROWSER_RETURN_URL=${KRATOS_UI_URL:-http://localhost:5000}
+      - KRATOS_SELFSERVICE_ALLOWED_RETURN_URLS=["${KRATOS_UI_URL:-http://localhost:5000}","${USERFRONT_URL:-http://localhost:5000}"]
+      - KRATOS_SELFSERVICE_FLOWS_ERROR_UI_URL=${KRATOS_UI_URL:-http://localhost:5000}/error
+      - KRATOS_SELFSERVICE_FLOWS_SETTINGS_UI_URL=${KRATOS_UI_URL:-http://localhost:5000}/error?error=settings_disabled
+      - KRATOS_SELFSERVICE_FLOWS_RECOVERY_UI_URL=${KRATOS_UI_URL:-http://localhost:5000}/recovery
+      - KRATOS_SELFSERVICE_FLOWS_VERIFICATION_UI_URL=${KRATOS_UI_URL:-http://localhost:5000}/verification
+      - KRATOS_SELFSERVICE_FLOWS_LOGIN_UI_URL=${KRATOS_UI_URL:-http://localhost:5000}/login
+      - KRATOS_SELFSERVICE_FLOWS_REGISTRATION_UI_URL=${KRATOS_UI_URL:-http://localhost:5000}/registration
+      - KRATOS_SELFSERVICE_FLOWS_LOGOUT_AFTER_DEFAULT_BROWSER_RETURN_URL=${KRATOS_UI_URL:-http://localhost:5000}/login
+    volumes:
+      - ./docker/ory/kratos:/etc/config/kratos
+    command: serve -c /etc/config/kratos/kratos.yml --dev --watch-courier
+    depends_on:
+      kratos-migrate:
+        condition: service_completed_successfully
+    networks:
+      - ory-net
+      - kratosnet
+
+  hydra-migrate:
+    image: oryd/hydra:${HYDRA_VERSION:-v25.4.0}
+    environment:
+      - DSN=postgres://${ORY_POSTGRES_USER}:${ORY_POSTGRES_PASSWORD}@postgres_ory:5432/${HYDRA_DB:-ory_hydra}?sslmode=disable&max_conns=20
+    command: migrate sql up -e --yes
+    depends_on:
+      postgres_ory:
+        condition: service_healthy
+    networks:
+      - ory-net
+
+  hydra:
+    image: oryd/hydra:${HYDRA_VERSION:-v25.4.0}
+    container_name: ory_hydra
+    environment:
+      - DSN=postgres://${ORY_POSTGRES_USER}:${ORY_POSTGRES_PASSWORD}@postgres_ory:5432/${HYDRA_DB:-ory_hydra}?sslmode=disable&max_conns=20
+      - URLS_SELF_ISSUER=${USERFRONT_URL:-http://localhost:5000}/oidc
+      - URLS_LOGIN=${USERFRONT_URL:-http://localhost:5000}/login
+      - URLS_CONSENT=${USERFRONT_URL:-http://localhost:5000}/consent
+      - SECRETS_SYSTEM=${ORY_POSTGRES_PASSWORD}
+    volumes:
+      - ./docker/ory/hydra:/etc/config/hydra
+    command: serve -c /etc/config/hydra/hydra.yml all --dev
+    depends_on:
+      hydra-migrate:
+        condition: service_completed_successfully
+    networks:
+      - ory-net
+      - hydranet
+
+  keto-migrate:
+    image: oryd/keto:${KETO_VERSION:-v25.4.0}
+    environment:
+      - DSN=postgres://${ORY_POSTGRES_USER}:${ORY_POSTGRES_PASSWORD}@postgres_ory:5432/${KETO_DB:-ory_keto}?sslmode=disable&max_conns=20
+    volumes:
+      - ./docker/ory/keto:/etc/config/keto
+    command: ["migrate", "up", "-c", "/etc/config/keto/keto.yml", "--yes"]
+    depends_on:
+      postgres_ory:
+        condition: service_healthy
+    networks:
+      - ory-net
+
+  keto:
+    image: oryd/keto:${KETO_VERSION:-v25.4.0}
+    container_name: ory_keto
+    environment:
+      - DSN=postgres://${ORY_POSTGRES_USER}:${ORY_POSTGRES_PASSWORD}@postgres_ory:5432/${KETO_DB:-ory_keto}?sslmode=disable&max_conns=20
+    volumes:
+      - ./docker/ory/keto:/etc/config/keto
+    command: serve -c /etc/config/keto/keto.yml
+    depends_on:
+      keto-migrate:
+        condition: service_completed_successfully
+    networks:
+      - ory-net
+
+  oathkeeper:
+    image: oryd/oathkeeper:${OATHKEEPER_VERSION:-v0.40.6}
+    container_name: oathkeeper
+    restart: unless-stopped
+    depends_on:
+      kratos:
+        condition: service_started
+    environment:
+      - LOG_LEVEL=debug
+    command: serve proxy --config /etc/config/oathkeeper/oathkeeper.yml
+    volumes:
+      - ./docker/ory/oathkeeper:/etc/config/oathkeeper
+      - oathkeeper_logs:/var/log/oathkeeper
+    networks:
+      - ory-net
+      - baron_net
+      - public_net
+    ports:
+      - "4455:4455"
+      - "4456:4456"
+    healthcheck:
+      test: ["CMD", "wget", "-qO-", "http://127.0.0.1:4456/health/ready"]
+      interval: 5s
+      timeout: 5s
+      retries: 5
+
+  ory_clickhouse:
+    image: clickhouse/clickhouse-server:latest
+    container_name: ory_clickhouse
+    environment:
+      - CLICKHOUSE_USER=${ORY_CLICKHOUSE_USER:-ory}
+      - CLICKHOUSE_PASSWORD=${ORY_CLICKHOUSE_PASSWORD:-orypass}
+    volumes:
+      - ory_clickhouse_data:/var/lib/clickhouse
+      - ./docker/ory/clickhouse:/docker-entrypoint-initdb.d
+    networks:
+      - ory-net
+
+  backend:
+    build:
+      context: ./backend
+      dockerfile: Dockerfile
+    container_name: baron_backend
+    env_file:
+      - .env
+    environment:
+      - APP_ENV=${APP_ENV:-development}
+      - GO_ENV=${APP_ENV:-development}
+      - COOKIE_SECRET=${COOKIE_SECRET}
+      - JWT_SECRET=${JWT_SECRET}
+      - DESCOPE_PROJECT_ID=${DESCOPE_PROJECT_ID:-}
+      - DESCOPE_MANAGEMENT_KEY=${DESCOPE_MANAGEMENT_KEY:-}
+      - NAVER_CLOUD_ACCESS_KEY=${NAVER_CLOUD_ACCESS_KEY}
+      - NAVER_CLOUD_SECRET_KEY=${NAVER_CLOUD_SECRET_KEY}
+      - NAVER_CLOUD_SERVICE_ID=${NAVER_CLOUD_SERVICE_ID}
+      - NAVER_SENDER_PHONE_NUMBER=${NAVER_SENDER_PHONE_NUMBER}
+      - USERFRONT_URL=${USERFRONT_URL}
+      - REDIS_ADDR=${REDIS_ADDR}
+      - IDP_PROVIDER=${IDP_PROVIDER:-ory}
+      - KRATOS_ADMIN_URL=${KRATOS_ADMIN_URL:-http://kratos:4434}
+      - HYDRA_ADMIN_URL=${HYDRA_ADMIN_URL:-http://hydra:4445}
+      - HYDRA_PUBLIC_URL=${HYDRA_PUBLIC_URL:-http://hydra:4444}
+      - DB_HOST=postgres
+      - CLICKHOUSE_HOST=clickhouse
+      - CLICKHOUSE_PORT=${CLICKHOUSE_PORT_NATIVE:-9000}
+      - CLICKHOUSE_USER=${CLICKHOUSE_USER:-baron}
+      - CLICKHOUSE_PASSWORD=${CLICKHOUSE_PASSWORD:-password}
+    depends_on:
+      clickhouse:
+        condition: service_healthy
+      redis:
+        condition: service_healthy
+      oathkeeper:
+        condition: service_healthy
+      kratos:
+        condition: service_started
+      hydra:
+        condition: service_started
+      keto:
+        condition: service_started
+      infra_check:
+        condition: service_started
+    networks:
+      - baron_net
+      - ory-net
+    volumes:
+      - ./backend:/app
+    command: ["go", "run", "./cmd/server"]
+    healthcheck:
+      test: ["CMD", "wget", "-qO-", "http://127.0.0.1:3000/health"]
+      interval: 10s
+      timeout: 5s
+      retries: 3
+      start_period: 10s
+
+  adminfront:
+    build:
+      context: ./adminfront
+      dockerfile: Dockerfile
+    container_name: baron_adminfront
+    env_file:
+      - .env
+    environment:
+      - APP_ENV=${APP_ENV:-development}
+      - API_PROXY_TARGET=http://baron_backend:3000
+    ports:
+      - "${ADMIN_PORT:-5173}:5173"
+    volumes:
+      - ./adminfront:/app
+      - /app/node_modules
+    networks:
+      - baron_net
+
+  devfront:
+    build:
+      context: ./devfront
+      dockerfile: Dockerfile
+    container_name: baron_devfront
+    env_file:
+      - .env
+    environment:
+      - APP_ENV=${APP_ENV:-development}
+      - API_PROXY_TARGET=http://baron_backend:3000
+    ports:
+      - "${DEVFRONT_PORT:-5174}:5173"
+    volumes:
+      - ./devfront:/app
+      - /app/node_modules
+    networks:
+      - baron_net
+
+  userfront:
+    build:
+      context: .
+      dockerfile: userfront/Dockerfile
+    container_name: baron_userfront
+    env_file:
+      - .env
+    environment:
+      - BACKEND_URL=${BACKEND_URL:-}
+      - USERFRONT_URL=${USERFRONT_URL}
+      - APP_ENV=${APP_ENV}
+    networks:
+      - baron_net
+      - ory-net
+    depends_on:
+      backend:
+        condition: service_healthy
+    command: >
+      /bin/sh -c "mkdir -p /usr/share/nginx/html/assets &&
+                  echo \"BACKEND_URL=$${BACKEND_URL}\" >> /usr/share/nginx/html/assets/.env &&
+                  echo \"USERFRONT_URL=$${USERFRONT_URL}\" >> /usr/share/nginx/html/assets/.env &&
+                  echo \"APP_ENV=$${APP_ENV}\" >> /usr/share/nginx/html/assets/.env &&
+                  cp /usr/share/nginx/html/assets/.env /usr/share/nginx/html/.env &&
+                  nginx -g 'daemon off;'"
+    healthcheck:
+      test: ["CMD", "wget", "-qO-", "http://127.0.0.1:5000/"]
+      interval: 10s
+      timeout: 5s
+      retries: 3
+      start_period: 10s
+
+  infra_check:
+    image: alpine
+    command: ["echo", "Infrastructure assumed running"]
+    networks:
+      - baron_net
+
+volumes:
+  postgres_data:
+  clickhouse_data:
+  redis_data:
+  ory_postgres_data:
+  ory_clickhouse_data:
+  oathkeeper_logs:
+
+networks:
+  baron_net:
+    external: true
+    name: baron_net
+  public_net:
+    external: true
+    name: public_net
+  ory-net:
+    external: true
+    name: ory-net
+  hydranet:
+    external: true
+    name: hydranet
+  kratosnet:
+    external: true
+    name: kratosnet
--- a/docs/SoT_Architecture_Policy.md
+++ b/docs/SoT_Architecture_Policy.md
@@ -0,0 +1,44 @@
+# Baron SSO Data SoT (Source of Truth) Architecture Policy
+
+## 1. Core Principle: "Ory Stack is the Single Source of Truth"
+Baron SSO 시스템에서 인증(Identity), 인가(Authorization), OAuth2 위임(Delegation)의 데이터 원천은 **Ory Stack (Kratos, Keto, Hydra)** 입니다.
+Backend의 로컬 데이터베이스(PostgreSQL)는 성능 최적화, 검색, 감사(Audit), 비즈니스 메타데이터 관리를 위한 **Read-Model** 및 **Cold Storage**의 역할만 수행합니다.
+
+## 2. Component Policies
+
+### 2.1 Identity & User Profile (Ory Kratos)
+*   **SoT:** Ory Kratos Identity (`traits`, `metadata_public`)
+*   **Local DB (`users` Table):** **Read-Model & Search Index**
+    *   **목적:** 대규모 사용자 목록의 고속 검색(`LIKE`), 필터링, 정렬, 테넌트 조인(Join) 지원.
+    *   **동기화 전략:** `Async Write-Behind`
+        *   사용자 생성/수정 API는 Kratos 처리가 성공하면 즉시 성공 응답을 반환합니다.
+        *   로컬 DB 동기화는 별도 고루틴(Goroutine)에서 비동기로 수행됩니다.
+    *   **장애 격리:** 로컬 DB 장애가 사용자의 로그인/가입 프로세스를 차단하지 않습니다.
+
+### 2.2 Permissions & Relationships (Ory Keto)
+*   **SoT:** Ory Keto (Relation Tuples)
+*   **Local DB:**
+    *   권한 판단 로직을 로컬 DB에 저장하지 않습니다.
+    *   `Tenant`, `TenantGroup` 등 비즈니스 객체의 **생성/삭제 이벤트**를 Keto의 관계(Relation)로 비동기 동기화합니다.
+    *   모든 권한 검증(`CheckPermission`)은 반드시 Keto API를 통해 실시간으로 수행합니다.
+
+### 2.3 OAuth2 Clients & Sessions (Ory Hydra)
+*   **SoT:** Ory Hydra (OAuth2 Clients, Access/Refresh Tokens, Consent Sessions)
+*   **Local DB (`client_secrets`, `client_consents`):** **Backup & Query-Model**
+    *   `client_secrets`: Hydra는 해시된 시크릿만 저장하므로, 시크릿 재발급 및 관리를 위한 **원본 보관소(Cold Storage)**로 사용합니다.
+    *   `client_consents`: Hydra API는 "특정 사용자의 동의 내역" 조회만 지원하므로, "특정 클라이언트의 전체 사용자 동의 목록"을 제공하기 위한 **조회용 모델(Query-Model)**로 사용합니다.
+
+## 3. Data Flow & Synchronization Strategy
+
+### 3.1 Write Path (Command)
+1.  **Request:** 클라이언트가 Backend API 요청.
+2.  **Ory Exec:** Backend가 Ory 서비스(Kratos/Hydra/Keto) API를 동기(Synchronous) 호출.
+3.  **Response:** Ory 성공 시 클라이언트에게 즉시 성공 응답 반환 (SoT 확정).
+4.  **Sync:** Backend가 비동기(Goroutine)로 로컬 DB 테이블을 갱신.
+
+### 3.2 Read Path (Query)
+*   **Self Context (내 정보, 내 권한):** Ory Session/Token을 통해 직접 검증하거나 Kratos/Keto를 실시간 조회 (Always Fresh).
+*   **Admin Context (목록 조회, 검색):** 로컬 DB를 조회하여 빠른 응답 제공 (Eventually Consistent).
+
+### 3.3 Conflict Resolution
+*   데이터 불일치가 발견될 경우, 항상 **Ory Stack의 데이터를 기준(Authority)**으로 로컬 DB를 보정(Self-healing)합니다.
--- a/docs/i18n.md
+++ b/docs/i18n.md
@@ -79,6 +79,7 @@ TOML에서는 `[Section]`을 사용하여 계층을 표현합니다.
    *   `ko` 계열이면 `/ko/dashboard`로 리다이렉트합니다.
    *   그 외에는 `/en/dashboard`로 리다이렉트합니다.
    *   *단, 이전에 언어를 선택한 쿠키나 로컬스토리지 값이 있다면 그 값을 우선합니다.*
+    *   로컬스토리지 키는 **`locale`**을 사용합니다.
 2.  **언어 변경 시**:
    *   모든 화면에는 **언어 선택기(Language Selector)**가 노출되어야 합니다.
    *   변경 시 해당 언어의 URL로 이동(`window.location` 변경 혹은 Router Push)하며, 선택된 언어를 로컬스토리지에 저장합니다.
--- a/docs/trouble-shooting/userfront-locale.md
+++ b/docs/trouble-shooting/userfront-locale.md
@@ -0,0 +1,86 @@
+# userfront locale 전환 문제 분석 및 대응
+
+## 증상
+- URL은 `/ko` ↔ `/en`으로 변경되지만 실제 텍스트가 바뀌지 않음.
+- 브라우저에서 `window.localStorage.getItem('locale')`가 계속 `null`.
+- 빌드/배포 후에도 동일 증상 유지.
+
+## 현재 구조 요약
+- Flutter Web + `easy_localization` 사용.
+- 경로 기반 로케일: `/:locale` 라우트 + `LocaleGate`로 로케일 적용.
+- 번역 리소스: `userfront/assets/translations/*.toml`.
+- 로케일 저장: `localStorage` key `locale`.
+
+## 이미 적용한 변경
+- `easy_localization` + TOML loader 적용.
+- `LocaleGate`에서 로케일 적용 및 저장.
+- `LanguageSelector`에서 로케일 저장 + URL 변경.
+- `userfront/assets/translations`에 `en.toml`, `ko.toml`, `template.toml` 포함.
+- `pubspec.yaml` assets 등록.
+- GoRouter 호환성 수정(빌드 오류 대응).
+
+## 원인 후보(우선순위)
+1) **로케일 저장이 실제로 실행되지 않음**
+   - `LanguageSelector` 클릭 이벤트가 동작하지 않거나,
+   - `LocaleGate`가 호출되지 않는 라우트 진입(예: 라우트 변경 없이 SPA 상태만 변경).
+
+2) **서비스 워커/캐시로 인해 구 번들이 계속 로드됨**
+   - Flutter Web 기본 `flutter_service_worker.js`가 캐시를 고정.
+   - 기존 번들이 남아 `LocaleStorage.write()` 반영 전 코드가 계속 실행될 가능성.
+
+3) **번역 리소스 미로딩**
+   - `assets/translations/en.toml`, `ko.toml` 요청이 404 또는 미요청.
+   - Nginx 경로/정적 파일 설정에서 `assets/`가 누락된 경우.
+
+4) **en.toml 키 누락으로 fallback 문자열이 표시됨**
+   - UI에서 `tr(..., fallback: '한국어')`를 쓰는 경우,
+     en.toml에 키가 없으면 한국어가 그대로 노출됨.
+
+## 확인 방법(권장 순서)
+1) **로케일 저장 확인**
+   - 언어 변경 후 콘솔:
+     - `window.localStorage.getItem('locale')`
+   - `null`이면 저장 로직 실행 실패.
+
+2) **번역 리소스 요청 확인**
+   - DevTools Network에서:
+     - `/assets/translations/ko.toml`
+     - `/assets/translations/en.toml`
+   - 404 또는 미요청이면 assets 로딩 문제.
+
+3) **로케일 반영 확인**
+   - UI 내 임시 텍스트로 `context.locale.languageCode` 출력
+   - 로케일이 바뀌는데 텍스트가 그대로면 TOML 키 누락 가능성.
+
+4) **캐시 무효화**
+   - 하드 리로드(Shift+Reload)
+   - service worker 제거 후 재접속
+
+## 현재까지 실행한 대응
+- `LocaleGate`에서 로케일 동일 여부와 상관없이 `LocaleStorage.write()`가 실행되도록 수정.
+- 라우터 로케일 파싱/전환 로직 보강.
+- 번역 리소스 파일 배치 및 assets 등록.
+
+## 앞으로의 대응 계획
+1) **서비스 워커 캐시 무효화 전략**
+   - `flutter_service_worker.js` 버전 갱신 또는 Nginx 캐시 무력화 정책 적용.
+   - 배포 시 `index.html`/`flutter_service_worker.js` 캐시 제어 헤더 추가.
+
+2) **번역 파일 누락 방지**
+   - `scripts/sync_userfront_locales.sh`를 CI에서 자동 실행.
+   - en/ko 키 누락 검증 테스트 추가.
+
+3) **로케일 저장 검증**
+   - 언어 변경 후 `localStorage`에 값이 반드시 들어오는지 E2E 체크 추가.
+
+4) **fallback 사용 최소화**
+   - userfront에서 `fallback` 문자열(한국어) 남용 구간 정리.
+   - en.toml에 키가 없을 때 한국어가 보이는 현상 방지.
+
+## 참고 파일
+- `userfront/lib/core/i18n/locale_gate.dart`
+- `userfront/lib/core/widgets/language_selector.dart`
+- `userfront/lib/core/i18n/locale_storage_web.dart`
+- `userfront/lib/core/i18n/toml_asset_loader.dart`
+- `userfront/assets/translations/en.toml`
+- `userfront/assets/translations/ko.toml`
--- a/locales/en.toml
+++ b/locales/en.toml
@@ -43,6 +43,7 @@ missing = "Missing"
 [msg]

 [msg.admin]
+logout_confirm = "Are you sure you want to log out?"
 idp_env_prod = "IDP env: prod"
 scope_admin = "Scoped to /admin"
 session_ttl = "Session TTL: 15m admin"
@@ -354,7 +355,7 @@ title_with_code = "Title With Code"
 type = "Type"

 [msg.userfront.error.whitelist]
-$normalizedCode = "$NormalizedCode"
+settings_disabled = "Account settings are currently unavailable."

 [msg.userfront.forgot]
 description = "Description"
@@ -370,10 +371,10 @@ link_failed = "Link Failed"
 link_send_failed = "Link Send Failed"
 link_sent_email = "Link Sent Email"
 link_sent_phone = "Link Sent Phone"
-link_timeout = "Link Timeout"
-no_account = "No Account"
+link_timeout = "Time expired."
+no_account = "New to Baron?"
 oidc_failed = "OIDC Failed"
-qr_expired = "QR Expired"
+qr_expired = "Time expired."
 qr_init_failed = "QR Init Failed"
 qr_login_required = "QR Login Required"
 token_missing = "Token Missing"
@@ -381,7 +382,7 @@ verification_failed = "Verification Failed"

 [msg.userfront.login.link]
 approved = "Approved"
-helper = "Helper"
+helper = "Sending you a login link"
 missing_login_id = "Missing Login Id"
 missing_phone = "Missing Phone"
 resend_wait = "Resend Wait"
@@ -840,9 +841,6 @@ role = "ROLE"
 status = "STATUS"
 tenant_dept = "TENANT / DEPT"

-[ui.btn]
-cancel = "Cancel"
-save = "Save"

 [ui.common]
 add = "Add"
@@ -872,6 +870,9 @@ retry = "Retry"
 save = "Save"
 search = "Search"
 show_more = "Show More"
+language = "Language"
+language_ko = "한국어"
+language_en = "English"
 theme_dark = "Dark"
 theme_light = "Light"
 theme_toggle = "Theme Toggle"
@@ -1090,11 +1091,9 @@ title = "Stack readiness"
 plane = "Dev Plane"
 subtitle = "Manage your applications"

-[ui.nav]
-dashboard = "Dashboard"

 [ui.userfront]
-app_title = "App Title"
+app_title = "Baron SW Portal"

 [ui.userfront.app_label]
 admin_console = "Admin Console"
@@ -1164,7 +1163,7 @@ signup = "Signup"
 submit = "Submit"

 [ui.userfront.login.field]
-login_id = "Login Id"
+login_id = "Emain or Phone Number"
 password = "Password"

 [ui.userfront.login.link]
@@ -1178,7 +1177,7 @@ title = "Title"
 [ui.userfront.login.qr]
 expired = "Expired"
 refresh = "Refresh"
-remaining = "Remaining"
+remaining = "Remaining: {{time}}"

 [ui.userfront.login.short_code]
 digits = "Digits"
@@ -1187,9 +1186,9 @@ prefix = "Prefix"
 submit = "Submit"

 [ui.userfront.login.tabs]
-link = "Link"
+link = "Link/Code"
 password = "Password"
-qr = "QR"
+qr = "QR Code"

 [ui.userfront.login.unregistered]
 action = "Action"
@@ -1305,3 +1304,15 @@ verify = "Verify"

 [ui.userfront.signup.success]
 action = "Action"
+
+[ui.admin.nav]
+api_keys = "API Keys"
+audit_logs = "Audit Logs"
+auth_guard = "Auth Guard"
+logout = "Logout"
+overview = "Overview"
+relying_parties = "Apps (RP)"
+tenant_dashboard = "Tenant Dashboard"
+tenant_groups = "Tenant Groups"
+tenants = "Tenants"
+users = "Users"
--- a/locales/ko.toml
+++ b/locales/ko.toml
@@ -43,6 +43,7 @@ missing = "활성 세션이 없습니다."
 [msg]

 [msg.admin]
+logout_confirm = "로그아웃 하시겠습니까?"
 idp_env_prod = "IDP env: prod"
 scope_admin = "Scoped to /admin"
 session_ttl = "Session TTL: 15m admin"
@@ -354,7 +355,7 @@ title_with_code = "오류: {{code}}"
 type = "오류 종류: {{type}}"

 [msg.userfront.error.whitelist]
-$normalizedCode = "에러가 계속되면 관리자에게 문의해주세요"
+settings_disabled = "현재 계정 설정 화면은 준비 중입니다."

 [msg.userfront.forgot]
 description = "계정과 연결된 이메일 주소 또는 휴대폰 번호를 입력하시면, 비밀번호를 재설정할 수 있는 링크를 보내드립니다."
@@ -370,10 +371,10 @@ link_failed = "오류: {{error}}"
 link_send_failed = "전송 실패: {{error}}"
 link_sent_email = "입력하신 이메일로 로그인 링크를 보냈습니다."
 link_sent_phone = "입력하신 번호로 로그인 링크를 보냈습니다."
-link_timeout = "로그인 요청 시간이 초과되었습니다."
+link_timeout = "시간이 경과되었습니다."
 no_account = "계정이 없으신가요?"
 oidc_failed = "OIDC 로그인 처리에 실패했습니다. 다시 시도해 주세요."
-qr_expired = "QR 세션이 만료되었습니다."
+qr_expired = "시간이 경과되었습니다."
 qr_init_failed = "QR 초기화에 실패했습니다: {{error}}"
 qr_login_required = "로그인 한 상태여야 QR 스캔으로 로그인 할 수 있습니다"
 token_missing = "로그인 토큰을 확인할 수 없습니다."
@@ -840,9 +841,6 @@ role = "ROLE"
 status = "STATUS"
 tenant_dept = "TENANT / DEPT"

-[ui.btn]
-cancel = "취소"
-save = "저장"

 [ui.common]
 add = "추가"
@@ -872,6 +870,9 @@ retry = "다시 시도"
 save = "저장"
 search = "검색"
 show_more = "+ 더보기"
+language = "언어"
+language_ko = "한국어"
+language_en = "English"
 theme_dark = "Dark"
 theme_light = "Light"
 theme_toggle = "테마 전환"
@@ -1090,11 +1091,9 @@ title = "Stack readiness"
 plane = "Dev Plane"
 subtitle = "Manage your applications"

-[ui.nav]
-dashboard = "대시보드"

 [ui.userfront]
-app_title = "Baron 로그인"
+app_title = "Baron SW 포탈"

 [ui.userfront.app_label]
 admin_console = "Admin Console"
@@ -1305,3 +1304,15 @@ verify = "본인인증"

 [ui.userfront.signup.success]
 action = "로그인하기"
+
+[ui.admin.nav]
+api_keys = "API 키"
+audit_logs = "감사 로그"
+auth_guard = "인증 가드"
+logout = "로그아웃"
+overview = "개요"
+relying_parties = "애플리케이션(RP)"
+tenant_dashboard = "테넌트 대시보드"
+tenant_groups = "테넌트 그룹"
+tenants = "테넌트"
+users = "사용자"
--- a/locales/template.toml
+++ b/locales/template.toml
@@ -44,6 +44,7 @@ missing = ""

 [msg.admin]
 idp_env_prod = ""
+logout_confirm = ""
 scope_admin = ""
 session_ttl = ""
 tenant_headers = ""
@@ -354,7 +355,7 @@ title_with_code = ""
 type = ""

 [msg.userfront.error.whitelist]
-$normalizedCode = ""
+settings_disabled = ""

 [msg.userfront.forgot]
 description = ""
@@ -658,6 +659,18 @@ name = ""
 [ui.admin.header]
 plane = ""

+[ui.admin.nav]
+api_keys = ""
+audit_logs = ""
+auth_guard = ""
+logout = ""
+overview = ""
+relying_parties = ""
+tenant_dashboard = ""
+tenant_groups = ""
+tenants = ""
+users = ""
+
 [ui.admin.overview]
 kicker = ""
 title = ""
@@ -840,9 +853,6 @@ role = ""
 status = ""
 tenant_dept = ""

-[ui.btn]
-cancel = ""
-save = ""

 [ui.common]
 add = ""
@@ -872,6 +882,9 @@ retry = ""
 save = ""
 search = ""
 show_more = ""
+language = ""
+language_ko = ""
+language_en = ""
 theme_dark = ""
 theme_light = ""
 theme_toggle = ""
@@ -1090,8 +1103,6 @@ title = ""
 plane = ""
 subtitle = ""

-[ui.nav]
-dashboard = ""

 [ui.userfront]
 app_title = ""
@@ -1178,7 +1189,7 @@ title = ""
 [ui.userfront.login.qr]
 expired = ""
 refresh = ""
-remaining = ""
+remaining = "Remaining: {{time}}"

 [ui.userfront.login.short_code]
 digits = ""
--- a/scripts/sync_userfront_locales.sh
+++ b/scripts/sync_userfront_locales.sh
@@ -0,0 +1,47 @@
+#!/bin/sh
+set -e
+
+# 루트 locales/*.toml -> userfront/assets/translations/ 동기화
+# - userfront에서 사용하는 섹션만 추출
+# - {{param}} -> {param} 변환 (easy_localization 포맷)
+repo_root="$(cd "$(dirname "$0")/.." && pwd)"
+src_dir="$repo_root/locales"
+dest_dir="$repo_root/userfront/assets/translations"
+
+mkdir -p "$dest_dir"
+
+filter_toml() {
+  src_file="$1"
+  dest_file="$2"
+  awk '
+    function allowed(section) {
+      return section ~ /^(ui\.userfront|msg\.userfront|err\.userfront|ui\.common)(\.|$)/;
+    }
+    BEGIN { keep = 0; }
+    {
+      line = $0;
+      if (match(line, /^[[:space:]]*\[[^]]+\][[:space:]]*$/)) {
+        section = line;
+        gsub(/^[[:space:]]*\[/, "", section);
+        gsub(/\][[:space:]]*$/, "", section);
+        keep = allowed(section);
+        if (keep) {
+          print line;
+        }
+        next;
+      }
+      if (keep) {
+        print line;
+      }
+    }
+  ' "$src_file" \
+    | sed -E 's/\{\{[[:space:]]*([a-zA-Z0-9_]+)[[:space:]]*\}\}/{\1}/g' \
+    > "$dest_file"
+}
+
+for file in "$src_dir"/*.toml; do
+  base="$(basename "$file")"
+  filter_toml "$file" "$dest_dir/$base"
+done
+
+echo "Synced locales to userfront assets: $dest_dir"
--- a/tools/i18n-scanner/report.js
+++ b/tools/i18n-scanner/report.js
@@ -0,0 +1,237 @@
+#!/usr/bin/env node
+'use strict';
+
+const fs = require('fs');
+const path = require('path');
+
+const ROOT_DIR = process.cwd();
+const LOCALES_DIR = path.join(ROOT_DIR, 'locales');
+const TEMPLATE_PATH = path.join(LOCALES_DIR, 'template.toml');
+const LANG_FILES = ['ko.toml', 'en.toml'];
+
+const SKIP_DIRS = new Set([
+  '.git',
+  'node_modules',
+  'dist',
+  'build',
+  '.dart_tool',
+  '.idea',
+  '.vscode',
+  'coverage',
+  '.next',
+  '.cache',
+  'tmp',
+  'logs',
+]);
+
+const CODE_EXTENSIONS = new Set(['.ts', '.tsx', '.dart']);
+
+const CODE_PATTERNS = [
+  /\b(?:i18n\.)?t\s*\(\s*['"]([^'"]+)['"]/g,
+  /\btr\s*\(\s*['"]([^'"]+)['"]/g,
+  /['"]([^'"]+)['"]\s*\.tr\s*\(/g,
+];
+
+function readFileRequired(filePath) {
+  if (!fs.existsSync(filePath)) {
+    return { ok: false, error: `파일이 없습니다: ${filePath}` };
+  }
+  return { ok: true, value: fs.readFileSync(filePath, 'utf8') };
+}
+
+function parseTomlKeys(filePath) {
+  const result = readFileRequired(filePath);
+  if (!result.ok) {
+    return { ok: false, error: result.error, keys: new Set() };
+  }
+
+  const keys = new Set();
+  const lines = result.value.split(/\r?\n/);
+  let currentSection = [];
+
+  for (const rawLine of lines) {
+    const line = rawLine.trim();
+    if (!line || line.startsWith('#')) {
+      continue;
+    }
+
+    if (line.startsWith('[[') && line.endsWith(']]')) {
+      const sectionName = line.slice(2, -2).trim();
+      currentSection = sectionName
+        ? sectionName.split('.').map((p) => p.trim()).filter(Boolean)
+        : [];
+      continue;
+    }
+
+    if (line.startsWith('[') && line.endsWith(']')) {
+      const sectionName = line.slice(1, -1).trim();
+      currentSection = sectionName
+        ? sectionName.split('.').map((p) => p.trim()).filter(Boolean)
+        : [];
+      continue;
+    }
+
+    const eqIndex = line.indexOf('=');
+    if (eqIndex === -1) {
+      continue;
+    }
+
+    const key = line.slice(0, eqIndex).trim();
+    if (!key) {
+      continue;
+    }
+
+    const fullKey = [...currentSection, key].join('.');
+    keys.add(fullKey);
+  }
+
+  return { ok: true, keys };
+}
+
+function walkDir(dirPath, files) {
+  const entries = fs.readdirSync(dirPath, { withFileTypes: true });
+  for (const entry of entries) {
+    if (entry.isDirectory()) {
+      if (SKIP_DIRS.has(entry.name)) {
+        continue;
+      }
+      walkDir(path.join(dirPath, entry.name), files);
+      continue;
+    }
+
+    if (!entry.isFile()) {
+      continue;
+    }
+
+    const ext = path.extname(entry.name).toLowerCase();
+    if (!CODE_EXTENSIONS.has(ext)) {
+      continue;
+    }
+
+    files.push(path.join(dirPath, entry.name));
+  }
+}
+
+function collectCodeKeys() {
+  const files = [];
+  walkDir(ROOT_DIR, files);
+
+  const keys = new Set();
+  for (const filePath of files) {
+    const content = fs.readFileSync(filePath, 'utf8');
+    for (const pattern of CODE_PATTERNS) {
+      let match;
+      while ((match = pattern.exec(content)) !== null) {
+        if (match[1]) {
+          keys.add(match[1]);
+        }
+      }
+    }
+  }
+
+  return keys;
+}
+
+function difference(aSet, bSet) {
+  const result = [];
+  for (const item of aSet) {
+    if (!bSet.has(item)) {
+      result.push(item);
+    }
+  }
+  return result.sort();
+}
+
+function buildReport() {
+  const report = {
+    generated_at: new Date().toISOString(),
+    errors: [],
+    warnings: [],
+    details: {
+      missing_in_template: [],
+      missing_in_lang: {},
+      unused_in_template: [],
+    },
+  };
+
+  const templateResult = parseTomlKeys(TEMPLATE_PATH);
+  if (!templateResult.ok) {
+    report.errors.push(templateResult.error);
+    return report;
+  }
+
+  const templateKeys = templateResult.keys;
+  const codeKeys = collectCodeKeys();
+
+  const langKeyMap = new Map();
+  for (const fileName of LANG_FILES) {
+    const langPath = path.join(LOCALES_DIR, fileName);
+    const langResult = parseTomlKeys(langPath);
+    if (!langResult.ok) {
+      report.errors.push(langResult.error);
+      continue;
+    }
+    langKeyMap.set(fileName, langResult.keys);
+  }
+
+  for (const [fileName, langKeys] of langKeyMap.entries()) {
+    const missingInLang = difference(templateKeys, langKeys);
+    if (missingInLang.length > 0) {
+      report.errors.push(
+        `[Sync Error] ${fileName} 누락 키 ${missingInLang.length}개`,
+      );
+      report.details.missing_in_lang[fileName] = missingInLang;
+    }
+  }
+
+  const missingInTemplate = difference(codeKeys, templateKeys);
+  if (missingInTemplate.length > 0) {
+    report.errors.push(
+      `[Missing Key] template.toml 누락 키 ${missingInTemplate.length}개`,
+    );
+    report.details.missing_in_template = missingInTemplate;
+  }
+
+  const unusedInTemplate = difference(templateKeys, codeKeys);
+  if (unusedInTemplate.length > 0) {
+    report.warnings.push(
+      `[Unused Key] template.toml 미사용 키 ${unusedInTemplate.length}개`,
+    );
+    report.details.unused_in_template = unusedInTemplate;
+  }
+
+  return report;
+}
+
+function main() {
+  const report = buildReport();
+  const outDir = path.join(ROOT_DIR, 'reports');
+  if (!fs.existsSync(outDir)) {
+    fs.mkdirSync(outDir, { recursive: true });
+  }
+  const outPath = path.join(outDir, 'i18n-report.json');
+  fs.writeFileSync(outPath, JSON.stringify(report, null, 2));
+  const summaryPath = path.join(outDir, 'i18n-report.txt');
+
+  const lines = [];
+  lines.push(`generated_at: ${report.generated_at}`);
+  if (report.errors.length > 0) {
+    lines.push('errors:');
+    report.errors.forEach((err) => lines.push(`- ${err}`));
+  } else {
+    lines.push('errors: none');
+  }
+  if (report.warnings.length > 0) {
+    lines.push('warnings:');
+    report.warnings.forEach((warn) => lines.push(`- ${warn}`));
+  } else {
+    lines.push('warnings: none');
+  }
+  fs.writeFileSync(summaryPath, lines.join('\n'));
+
+  if (report.errors.length > 0) {
+    process.exit(1);
+  }
+}
+
+main();
--- a/userfront/Dockerfile
+++ b/userfront/Dockerfile
@@ -1,10 +1,11 @@
 # Stage 1: Build Flutter
-FROM ghcr.io/cirruslabs/flutter:stable AS build
+FROM ghcr.io/cirruslabs/flutter:3.38.0 AS build
 ENV RUN_FLUTTER_AS_ROOT=true
-# ENV RUN_FLUTTER_AS_ROOT=true
 WORKDIR /app
 COPY . .
 # Get dependencies and build for web
+RUN /bin/sh ./scripts/sync_userfront_locales.sh
+WORKDIR /app/userfront
 RUN flutter pub get
 RUN touch .env
 RUN flutter build web --release --no-tree-shake-icons --wasm
@@ -12,9 +13,9 @@ RUN flutter build web --release --no-tree-shake-icons --wasm
 # Stage 2: Serve with Nginx
 FROM nginx:alpine
 # Copy built assets
-COPY --from=build /app/build/web /usr/share/nginx/html
+COPY --from=build /app/userfront/build/web /usr/share/nginx/html
 # Copy custom Nginx config
-COPY nginx.conf /etc/nginx/conf.d/default.conf
+COPY userfront/nginx.conf /etc/nginx/conf.d/default.conf

 EXPOSE 5000
 CMD ["nginx", "-g", "daemon off;"]
--- a/userfront/assets/translations/en.toml
+++ b/userfront/assets/translations/en.toml
--- a/userfront/assets/translations/ko.toml
+++ b/userfront/assets/translations/ko.toml
--- a/userfront/assets/translations/template.toml
+++ b/userfront/assets/translations/template.toml
@@ -0,0 +1,536 @@
+[err.userfront]
+
+[err.userfront.auth_proxy]
+consent_accept = ""
+consent_fetch = ""
+consent_reject = ""
+linked_app_revoke = ""
+login_failed = ""
+oidc_accept = ""
+password_reset_complete = ""
+password_reset_init = ""
+
+[err.userfront.profile]
+load_failed = ""
+password_change_failed = ""
+send_code_failed = ""
+update_failed = ""
+verify_code_failed = ""
+
+[err.userfront.session]
+missing = ""
+
+[msg.userfront]
+greeting = ""
+
+[msg.userfront.audit]
+date = ""
+device = ""
+end = ""
+ip = ""
+load_more_error = ""
+result = ""
+session_id = ""
+status = ""
+
+[msg.userfront.dashboard]
+approved_device = ""
+approved_ip = ""
+audit_empty = ""
+audit_load_error = ""
+auth_method = ""
+client_id = ""
+client_id_missing = ""
+current_status = ""
+last_auth = ""
+link_missing = ""
+link_open_error = ""
+session_id_copied = ""
+
+[msg.userfront.dashboard.activities]
+empty = ""
+empty_detail = ""
+error = ""
+
+[msg.userfront.dashboard.approved_session]
+copy_click = ""
+copy_tap = ""
+none = ""
+
+[msg.userfront.dashboard.revoke]
+confirm = ""
+error = ""
+success = ""
+
+[msg.userfront.dashboard.scopes]
+empty = ""
+
+[msg.userfront.dashboard.timeline]
+load_error = ""
+
+[msg.userfront.error]
+detail_contact = ""
+detail_generic = ""
+detail_request = ""
+id = ""
+title = ""
+title_generic = ""
+title_with_code = ""
+type = ""
+
+[msg.userfront.error.whitelist]
+settings_disabled = ""
+
+[msg.userfront.forgot]
+description = ""
+dry_send = ""
+error = ""
+input_required = ""
+sent = ""
+
+[msg.userfront.login]
+cookie_check_failed = ""
+dry_send = ""
+link_failed = ""
+link_send_failed = ""
+link_sent_email = ""
+link_sent_phone = ""
+link_timeout = ""
+no_account = ""
+oidc_failed = ""
+qr_expired = ""
+qr_init_failed = ""
+qr_login_required = ""
+token_missing = ""
+verification_failed = ""
+
+[msg.userfront.login.link]
+approved = ""
+helper = ""
+missing_login_id = ""
+missing_phone = ""
+resend_wait = ""
+short_code_help = ""
+
+[msg.userfront.login.password]
+failed = ""
+missing_credentials = ""
+
+[msg.userfront.login.qr]
+load_failed = ""
+scan_hint = ""
+
+[msg.userfront.login.short_code]
+invalid = ""
+
+[msg.userfront.login.unregistered]
+body = ""
+
+[msg.userfront.login.verification]
+approved = ""
+approved_local = ""
+success = ""
+
+[msg.userfront.login_success]
+subtitle = ""
+
+[msg.userfront.profile]
+department_missing = ""
+department_required = ""
+email_missing = ""
+greeting = ""
+load_failed = ""
+name_missing = ""
+name_required = ""
+phone_required = ""
+phone_verify_required = ""
+update_failed = ""
+update_success = ""
+
+[msg.userfront.profile.password]
+change_failed = ""
+changed = ""
+current_required = ""
+mismatch = ""
+new_required = ""
+subtitle = ""
+
+[msg.userfront.profile.phone]
+code_sent = ""
+send_failed = ""
+verified = ""
+verify_failed = ""
+verify_notice = ""
+
+[msg.userfront.profile.section]
+basic = ""
+organization = ""
+security = ""
+
+[msg.userfront.qr]
+approve_error = ""
+approve_success = ""
+camera_error = ""
+permission_error = ""
+permission_required = ""
+
+[msg.userfront.reset]
+invalid_body = ""
+invalid_link = ""
+invalid_title = ""
+policy_loading = ""
+success = ""
+
+[msg.userfront.reset.error]
+empty_password = ""
+generic = ""
+lowercase = ""
+min_length = ""
+min_types = ""
+mismatch = ""
+number = ""
+symbol = ""
+uppercase = ""
+
+[msg.userfront.reset.policy]
+lowercase = ""
+min_length = ""
+min_types = ""
+number = ""
+symbol = ""
+uppercase = ""
+
+[msg.userfront.sections]
+apps_subtitle = ""
+audit_subtitle = ""
+
+[msg.userfront.settings]
+disabled = ""
+
+[msg.userfront.signup]
+failed = ""
+privacy_full = ""
+tos_full = ""
+
+[msg.userfront.signup.agreement]
+title = ""
+
+[msg.userfront.signup.auth]
+affiliate_notice = ""
+title = ""
+
+[msg.userfront.signup.email]
+code_mismatch = ""
+duplicate = ""
+invalid = ""
+send_failed = ""
+verified = ""
+verify_failed = ""
+
+[msg.userfront.signup.password]
+length_required = ""
+lowercase_required = ""
+mismatch = ""
+number_required = ""
+symbol_required = ""
+title = ""
+uppercase_required = ""
+
+[msg.userfront.signup.password.rule]
+lowercase = ""
+min_length = ""
+min_types = ""
+number = ""
+symbol = ""
+uppercase = ""
+
+[msg.userfront.signup.phone]
+code_mismatch = ""
+send_failed = ""
+verified = ""
+verify_failed = ""
+
+[msg.userfront.signup.policy]
+loading = ""
+lowercase = ""
+min_length = ""
+min_types = ""
+number = ""
+summary = ""
+symbol = ""
+uppercase = ""
+
+[msg.userfront.signup.profile]
+affiliate_hint = ""
+title = ""
+
+[msg.userfront.signup.success]
+body = ""
+title = ""
+
+[ui.common]
+add = ""
+back = ""
+cancel = ""
+close = ""
+collapse = ""
+confirm = ""
+copy = ""
+create = ""
+delete = ""
+details = ""
+edit = ""
+hyphen = ""
+na = ""
+never = ""
+next = ""
+page_of = ""
+prev = ""
+previous = ""
+qr = ""
+read_only = ""
+refresh = ""
+requesting = ""
+resend = ""
+retry = ""
+save = ""
+search = ""
+show_more = ""
+language = ""
+language_ko = ""
+language_en = ""
+theme_dark = ""
+theme_light = ""
+theme_toggle = ""
+unknown = ""
+
+[ui.common.badge]
+admin_only = ""
+command_only = ""
+system = ""
+
+[ui.common.role]
+admin = ""
+user = ""
+
+[ui.common.status]
+active = ""
+blocked = ""
+failure = ""
+inactive = ""
+ok = ""
+pending = ""
+success = ""
+
+[ui.userfront]
+app_title = ""
+
+[ui.userfront.app_label]
+admin_console = ""
+baron = ""
+dev_console = ""
+
+[ui.userfront.audit]
+
+[ui.userfront.audit.table]
+app = ""
+auth_method = ""
+date = ""
+device = ""
+ip = ""
+pending = ""
+result = ""
+session_id = ""
+status = ""
+
+[ui.userfront.auth_method]
+ory = ""
+session = ""
+
+[ui.userfront.dashboard]
+last_auth_label = ""
+status_history = ""
+
+[ui.userfront.dashboard.activity]
+linked = ""
+
+[ui.userfront.dashboard.approved_session]
+default = ""
+userfront = ""
+
+[ui.userfront.dashboard.revoke]
+confirm_button = ""
+title = ""
+
+[ui.userfront.dashboard.scopes]
+title = ""
+
+[ui.userfront.dashboard.status]
+revoked = ""
+
+[ui.userfront.device]
+android = ""
+ios = ""
+linux = ""
+macos = ""
+windows = ""
+
+[ui.userfront.error]
+go_home = ""
+go_login = ""
+
+[ui.userfront.forgot]
+heading = ""
+input_label = ""
+submit = ""
+title = ""
+
+[ui.userfront.login]
+forgot_password = ""
+signup = ""
+
+[ui.userfront.login.action]
+submit = ""
+
+[ui.userfront.login.field]
+login_id = ""
+password = ""
+
+[ui.userfront.login.link]
+action_label = ""
+code_only = ""
+page_title = ""
+resend_with_time = ""
+send = ""
+title = ""
+
+[ui.userfront.login.qr]
+expired = ""
+refresh = ""
+remaining = "Remaining: {time}"
+
+[ui.userfront.login.short_code]
+digits = ""
+expire_time = ""
+prefix = ""
+submit = ""
+
+[ui.userfront.login.tabs]
+link = ""
+password = ""
+qr = ""
+
+[ui.userfront.login.unregistered]
+action = ""
+title = ""
+
+[ui.userfront.login.verification]
+action_label = ""
+page_title = ""
+title = ""
+
+[ui.userfront.login_success]
+later = ""
+qr = ""
+title = ""
+
+[ui.userfront.nav]
+dashboard = ""
+logout = ""
+profile = ""
+qr_scan = ""
+
+[ui.userfront.profile]
+department_empty = ""
+manage = ""
+user_fallback = ""
+
+[ui.userfront.profile.field]
+affiliation = ""
+company_code = ""
+department = ""
+email = ""
+name = ""
+tenant = ""
+
+[ui.userfront.profile.password]
+change = ""
+confirm = ""
+current = ""
+forgot = ""
+new = ""
+title = ""
+
+[ui.userfront.profile.phone]
+code_hint = ""
+request_code = ""
+title = ""
+
+[ui.userfront.profile.section]
+basic = ""
+organization = ""
+security = ""
+
+[ui.userfront.qr]
+request_permission = ""
+rescan = ""
+result_failure = ""
+result_success = ""
+title = ""
+
+[ui.userfront.reset]
+confirm_password = ""
+new_password = ""
+submit = ""
+subtitle = ""
+title = ""
+
+[ui.userfront.sections]
+apps = ""
+audit = ""
+
+[ui.userfront.session]
+active = ""
+unknown = ""
+
+[ui.userfront.signup]
+complete = ""
+next_step = ""
+title = ""
+
+[ui.userfront.signup.agreement]
+all = ""
+privacy_title = ""
+tos_title = ""
+
+[ui.userfront.signup.auth]
+code_label = ""
+request_code = ""
+
+[ui.userfront.signup.auth.email]
+label = ""
+title = ""
+
+[ui.userfront.signup.password]
+confirm_label = ""
+label = ""
+
+[ui.userfront.signup.phone]
+label = ""
+title = ""
+
+[ui.userfront.signup.profile]
+affiliation_type = ""
+company = ""
+department = ""
+department_optional = ""
+name = ""
+
+[ui.userfront.signup.steps]
+agreement = ""
+password = ""
+profile = ""
+verify = ""
+
+[ui.userfront.signup.success]
+action = ""
--- a/userfront/lib/core/i18n/locale_gate.dart
+++ b/userfront/lib/core/i18n/locale_gate.dart
@@ -0,0 +1,51 @@
+import 'package:easy_localization/easy_localization.dart' hide tr;
+import 'package:flutter/material.dart';
+
+import 'package:userfront/i18n.dart';
+import '../services/web_window.dart';
+import 'locale_storage.dart';
+import 'locale_utils.dart';
+
+class LocaleGate extends StatefulWidget {
+  const LocaleGate({super.key, required this.localeCode, required this.child});
+
+  final String localeCode;
+  final Widget child;
+
+  @override
+  State<LocaleGate> createState() => _LocaleGateState();
+}
+
+class _LocaleGateState extends State<LocaleGate> {
+  @override
+  void didChangeDependencies() {
+    super.didChangeDependencies();
+    _applyLocale();
+  }
+
+  @override
+  void didUpdateWidget(LocaleGate oldWidget) {
+    super.didUpdateWidget(oldWidget);
+    if (oldWidget.localeCode != widget.localeCode) {
+      _applyLocale();
+    }
+  }
+
+  Future<void> _applyLocale() async {
+    final normalized = normalizeLocaleCode(widget.localeCode);
+    LocaleStorage.write(normalized);
+    webWindow.setTitle(
+      tr('ui.userfront.app_title'),
+    );
+    if (context.locale.languageCode == normalized) {
+      return;
+    }
+    await context.setLocale(Locale(normalized));
+    webWindow.setTitle(
+      tr('ui.userfront.app_title'),
+    );
+  }
+
+  @override
+  Widget build(BuildContext context) => widget.child;
+}
--- a/userfront/lib/core/i18n/locale_storage.dart
+++ b/userfront/lib/core/i18n/locale_storage.dart
@@ -0,0 +1,7 @@
+import 'locale_storage_stub.dart'
+    if (dart.library.html) 'locale_storage_web.dart';
+
+abstract class LocaleStorage {
+  static String? read() => localeStorage.read();
+  static void write(String locale) => localeStorage.write(locale);
+}
--- a/userfront/lib/core/i18n/locale_storage_stub.dart
+++ b/userfront/lib/core/i18n/locale_storage_stub.dart
@@ -0,0 +1,11 @@
+class LocaleStorageImpl {
+  String? _locale;
+
+  String? read() => _locale;
+
+  void write(String locale) {
+    _locale = locale;
+  }
+}
+
+final localeStorage = LocaleStorageImpl();
--- a/userfront/lib/core/i18n/locale_storage_web.dart
+++ b/userfront/lib/core/i18n/locale_storage_web.dart
@@ -0,0 +1,120 @@
+// ignore_for_file: avoid_web_libraries_in_flutter
+
+import 'dart:html' as html;
+import 'package:flutter/foundation.dart';
+
+class LocaleStorageImpl {
+  static const _key = 'locale';
+  static const _legacyKey = 'baron_locale';
+  static final Map<String, String> _memory = {};
+  static bool _forceMemory = false;
+  static bool _forceSession = false;
+
+  @visibleForTesting
+  static void forceMemoryStorageForTests(bool value) {
+    _forceMemory = value;
+    if (!value) {
+      _memory.clear();
+    }
+  }
+
+  @visibleForTesting
+  static void forceSessionStorageForTests(bool value) {
+    _forceSession = value;
+  }
+
+  String? _read(String key) {
+    if (!_forceMemory && !_forceSession) {
+      try {
+        return html.window.localStorage[key];
+      } catch (_) {
+        // localStorage 접근이 차단된 경우 sessionStorage로 fallback.
+        try {
+          return html.window.sessionStorage[key];
+        } catch (_) {
+          // sessionStorage도 차단된 경우 메모리 fallback 사용.
+        }
+      }
+    }
+    if (!_forceMemory) {
+      try {
+        return html.window.sessionStorage[key];
+      } catch (_) {
+        // sessionStorage도 차단된 경우 메모리 fallback 사용.
+      }
+    }
+    return _memory[key];
+  }
+
+  void _write(String key, String value) {
+    if (!_forceMemory && !_forceSession) {
+      try {
+        html.window.localStorage[key] = value;
+        return;
+      } catch (_) {
+        // localStorage 접근이 차단된 경우 sessionStorage로 fallback.
+        try {
+          html.window.sessionStorage[key] = value;
+          return;
+        } catch (_) {
+          // sessionStorage도 차단된 경우 메모리 fallback 사용.
+        }
+      }
+    }
+    if (!_forceMemory) {
+      try {
+        html.window.sessionStorage[key] = value;
+        return;
+      } catch (_) {
+        // sessionStorage도 차단된 경우 메모리 fallback 사용.
+      }
+    }
+    _memory[key] = value;
+  }
+
+  void _remove(String key) {
+    if (!_forceMemory && !_forceSession) {
+      try {
+        html.window.localStorage.remove(key);
+        return;
+      } catch (_) {
+        // localStorage 접근이 차단된 경우 sessionStorage로 fallback.
+        try {
+          html.window.sessionStorage.remove(key);
+          return;
+        } catch (_) {
+          // sessionStorage도 차단된 경우 메모리 fallback 사용.
+        }
+      }
+    }
+    if (!_forceMemory) {
+      try {
+        html.window.sessionStorage.remove(key);
+        return;
+      } catch (_) {
+        // sessionStorage도 차단된 경우 메모리 fallback 사용.
+      }
+    }
+    _memory.remove(key);
+  }
+
+  String? read() {
+    final current = _read(_key);
+    if (current != null && current.isNotEmpty) {
+      return current;
+    }
+    final legacy = _read(_legacyKey);
+    if (legacy != null && legacy.isNotEmpty) {
+      _write(_key, legacy);
+      _remove(_legacyKey);
+      return legacy;
+    }
+    return null;
+  }
+
+  void write(String locale) {
+    _write(_key, locale);
+  }
+}
+
+final localeStorage = LocaleStorageImpl();
--- a/userfront/lib/core/i18n/locale_utils.dart
+++ b/userfront/lib/core/i18n/locale_utils.dart
@@ -0,0 +1,69 @@
+import 'dart:ui';
+
+import 'locale_storage.dart';
+
+const supportedLocaleCodes = ['en', 'ko'];
+const defaultLocaleCode = 'en';
+
+String normalizeLocaleCode(String? code) {
+  if (code == null || code.isEmpty) {
+    return defaultLocaleCode;
+  }
+  final normalized = code.toLowerCase();
+  if (normalized == 'ko' || normalized.startsWith('ko-')) {
+    return 'ko';
+  }
+  if (normalized == 'en' || normalized.startsWith('en-')) {
+    return 'en';
+  }
+  return defaultLocaleCode;
+}
+
+String resolvePreferredLocaleCode() {
+  final stored = LocaleStorage.read();
+  if (stored != null && supportedLocaleCodes.contains(stored)) {
+    return stored;
+  }
+  final deviceLocale = PlatformDispatcher.instance.locale;
+  return normalizeLocaleCode(deviceLocale.languageCode);
+}
+
+String? extractLocaleFromPath(Uri uri) {
+  if (uri.pathSegments.isEmpty) {
+    return null;
+  }
+  final code = uri.pathSegments.first.toLowerCase();
+  if (supportedLocaleCodes.contains(code)) {
+    return code;
+  }
+  return null;
+}
+
+String stripLocalePath(Uri uri) {
+  final segments = uri.pathSegments;
+  if (segments.isNotEmpty && supportedLocaleCodes.contains(segments.first)) {
+    final rest = segments.skip(1).join('/');
+    if (rest.isEmpty) {
+      return '/';
+    }
+    return '/$rest';
+  }
+  return uri.path;
+}
+
+String buildLocalizedPath(String localeCode, Uri uri) {
+  final segments = uri.pathSegments;
+  Iterable<String> restSegments = segments;
+  if (segments.isNotEmpty) {
+    final head = segments.first.toLowerCase();
+    if (supportedLocaleCodes.contains(head) || head.length == 2) {
+      restSegments = segments.skip(1);
+    }
+  }
+  final newSegments = [localeCode, ...restSegments];
+  final path = '/${newSegments.join('/')}';
+  if (uri.queryParameters.isEmpty) {
+    return path;
+  }
+  return Uri(path: path, queryParameters: uri.queryParameters).toString();
+}
--- a/userfront/lib/core/i18n/toml_asset_loader.dart
+++ b/userfront/lib/core/i18n/toml_asset_loader.dart
@@ -0,0 +1,22 @@
+import 'dart:ui';
+
+import 'package:easy_localization/easy_localization.dart';
+import 'package:flutter/services.dart';
+import 'package:toml/toml.dart';
+
+class TomlAssetLoader extends AssetLoader {
+  const TomlAssetLoader();
+
+  @override
+  Future<Map<String, dynamic>> load(String path, Locale locale) async {
+    final assetPath = '$path/${locale.languageCode}.toml';
+    try {
+      final content = await rootBundle.loadString(assetPath);
+      final document = TomlDocument.parse(content);
+      return document.toMap();
+    } catch (e) {
+      // 로딩 실패 시 빈 맵을 반환해 렌더링을 지속합니다.
+      return {};
+    }
+  }
+}
--- a/userfront/lib/core/services/auth_proxy_service.dart
+++ b/userfront/lib/core/services/auth_proxy_service.dart
@@ -11,18 +11,34 @@ class AuthProxyService {
    if (!dotenv.isInitialized) {
      return fallback;
    }
-    return dotenv.env[key] ?? fallback;
+    final value = dotenv.env[key];
+    if (value == null || value.trim().isEmpty) {
+      return fallback;
+    }
+    return value;
+  }
+
+  static String _fallbackOrigin() {
+    try {
+      final origin = Uri.base.origin;
+      if (origin.isNotEmpty && origin != 'null') {
+        return origin;
+      }
+    } catch (_) {}
+    return 'http://sso.hmac.kr';
  }

  static String get _baseUrl {
-    final rawUrl = _envOrDefault('BACKEND_URL', 'https://sso.hmac.kr');
+    final rawUrl = _envOrDefault('BACKEND_URL', _fallbackOrigin());
    // 배포 환경에서 $ 기호나 공백이 섞여 들어오는 경우를 방지하기 위해 정제합니다.
    return rawUrl.replaceAll(r'$', '').trim().replaceAll(RegExp(r'/$'), '');
  }
+
  static bool get _isProd {
    final env = _envOrDefault('APP_ENV', 'dev').toLowerCase();
    return env == 'prod' || env == 'production';
  }
+
  static bool get isProdEnv => _isProd;
  static bool _shouldSendDrySend(bool? drySend) {
    if (_isProd) {
@@ -76,13 +92,14 @@ class AuthProxyService {
    }
  }

-  static Future<int> getSessionStatus({String? token, bool useCookie = false}) async {
+  static Future<int> getSessionStatus({
+    String? token,
+    bool useCookie = false,
+  }) async {
    final url = Uri.parse('$_baseUrl/api/v1/user/me');
    final client = createHttpClient(withCredentials: useCookie);
    try {
-      final headers = <String, String>{
-        'Content-Type': 'application/json',
-      };
+      final headers = <String, String>{'Content-Type': 'application/json'};
      if (!useCookie && token != null && token.isNotEmpty) {
        headers['Authorization'] = 'Bearer $token';
      }
@@ -100,12 +117,9 @@ class AuthProxyService {
    bool? drySend,
  }) async {
    final url = Uri.parse('$_baseUrl/api/v1/auth/enchanted-link/init');
-    final userfrontUrl = _envOrDefault('USERFRONT_URL', 'http://sso.hmac.kr');
-    
-    final body = <String, dynamic>{
-      'loginId': loginId,
-      'uri': userfrontUrl,
-    };
+    final userfrontUrl = _envOrDefault('USERFRONT_URL', _fallbackOrigin());
+
+    final body = <String, dynamic>{'loginId': loginId, 'uri': userfrontUrl};
    if (_shouldSendDrySend(drySend)) {
      body['drySend'] = true;
    }
@@ -115,7 +129,7 @@ class AuthProxyService {
    if (codeOnly == true) {
      body['codeOnly'] = true;
    }
-    
+
    final response = await http.post(
      url,
      headers: {'Content-Type': 'application/json'},
@@ -133,15 +147,15 @@ class AuthProxyService {
    }
  }

-  static Future<Map<String, dynamic>> pollEnchantedLink(String pendingRef) async {
+  static Future<Map<String, dynamic>> pollEnchantedLink(
+    String pendingRef,
+  ) async {
    final url = Uri.parse('$_baseUrl/api/v1/auth/enchanted-link/poll');
-    
+
    final response = await http.post(
      url,
      headers: {'Content-Type': 'application/json'},
-      body: jsonEncode({
-        'pendingRef': pendingRef,
-      }),
+      body: jsonEncode({'pendingRef': pendingRef}),
    );

    if (response.statusCode == 200) {
@@ -157,16 +171,16 @@ class AuthProxyService {
    );
  }

-  static Future<Map<String, dynamic>> verifyMagicLink(String token, {bool verifyOnly = false}) async {
+  static Future<Map<String, dynamic>> verifyMagicLink(
+    String token, {
+    bool verifyOnly = false,
+  }) async {
    final url = Uri.parse('$_baseUrl/api/v1/auth/magic-link/verify');
-    
+
    final response = await http.post(
      url,
      headers: {'Content-Type': 'application/json'},
-      body: jsonEncode({
-        'token': token,
-        'verifyOnly': verifyOnly,
-      }),
+      body: jsonEncode({'token': token, 'verifyOnly': verifyOnly}),
    );

    if (response.statusCode == 200) {
@@ -223,10 +237,7 @@ class AuthProxyService {
    final response = await http.post(
      url,
      headers: {'Content-Type': 'application/json'},
-      body: jsonEncode({
-        'shortCode': shortCode,
-        'verifyOnly': verifyOnly,
-      }),
+      body: jsonEncode({'shortCode': shortCode, 'verifyOnly': verifyOnly}),
    );

    if (response.statusCode == 200) {
@@ -240,13 +251,18 @@ class AuthProxyService {
    }
  }

-  static Future<Map<String, dynamic>> loginWithPassword(String loginId, String password, {String? loginChallenge}) async {
+  static Future<Map<String, dynamic>> loginWithPassword(
+    String loginId,
+    String password, {
+    String? loginChallenge,
+  }) async {
    final url = Uri.parse('$_baseUrl/api/v1/auth/password/login');
-    
+
    final payload = {
      'loginId': loginId,
      'password': password,
-      if (loginChallenge != null && loginChallenge.isNotEmpty) 'login_challenge': loginChallenge,
+      if (loginChallenge != null && loginChallenge.isNotEmpty)
+        'login_challenge': loginChallenge,
    };

    final response = await http.post(
@@ -267,13 +283,17 @@ class AuthProxyService {
        errorBody['error'] ??
            tr(
              'err.userfront.auth_proxy.login_failed',
-              fallback: '로그인에 실패했습니다.',
            ),
      );
    }
  }
-  static Future<Map<String, dynamic>> getConsentInfo(String consentChallenge) async {
-    final url = Uri.parse('$_baseUrl/api/v1/auth/consent').replace(queryParameters: {'consent_challenge': consentChallenge});
+
+  static Future<Map<String, dynamic>> getConsentInfo(
+    String consentChallenge,
+  ) async {
+    final url = Uri.parse(
+      '$_baseUrl/api/v1/auth/consent',
+    ).replace(queryParameters: {'consent_challenge': consentChallenge});
    final response = await http.get(
      url,
      headers: {'Content-Type': 'application/json'},
@@ -287,17 +307,17 @@ class AuthProxyService {
        errorBody['error'] ??
            tr(
              'err.userfront.auth_proxy.consent_fetch',
-              fallback: '동의 정보를 가져오지 못했습니다.',
            ),
      );
    }
  }

-  static Future<Map<String, dynamic>> acceptConsent(String consentChallenge, {List<String>? grantScope}) async {
+  static Future<Map<String, dynamic>> acceptConsent(
+    String consentChallenge, {
+    List<String>? grantScope,
+  }) async {
    final url = Uri.parse('$_baseUrl/api/v1/auth/consent/accept');
-    final body = <String, dynamic>{
-      'consent_challenge': consentChallenge,
-    };
+    final body = <String, dynamic>{'consent_challenge': consentChallenge};
    if (grantScope != null) {
      body['grant_scope'] = grantScope;
    }
@@ -316,17 +336,16 @@ class AuthProxyService {
        errorBody['error'] ??
            tr(
              'err.userfront.auth_proxy.consent_accept',
-              fallback: '동의 처리에 실패했습니다.',
            ),
      );
    }
  }

-  static Future<Map<String, dynamic>> rejectConsent(String consentChallenge) async {
+  static Future<Map<String, dynamic>> rejectConsent(
+    String consentChallenge,
+  ) async {
    final url = Uri.parse('$_baseUrl/api/v1/auth/consent/reject');
-    final body = <String, dynamic>{
-      'consent_challenge': consentChallenge,
-    };
+    final body = <String, dynamic>{'consent_challenge': consentChallenge};

    final response = await http.post(
      url,
@@ -342,7 +361,6 @@ class AuthProxyService {
        errorBody['error'] ??
            tr(
              'err.userfront.auth_proxy.consent_reject',
-              fallback: '동의 거부에 실패했습니다.',
            ),
      );
    }
@@ -353,9 +371,7 @@ class AuthProxyService {
    String? token,
  }) async {
    final url = Uri.parse('$_baseUrl/api/v1/auth/oidc/login/accept');
-    final headers = <String, String>{
-      'Content-Type': 'application/json',
-    };
+    final headers = <String, String>{'Content-Type': 'application/json'};
    if (token != null && token.isNotEmpty) {
      headers['Authorization'] = 'Bearer $token';
    }
@@ -364,9 +380,7 @@ class AuthProxyService {
      final response = await client.post(
        url,
        headers: headers,
-        body: jsonEncode({
-          'login_challenge': loginChallenge,
-        }),
+        body: jsonEncode({'login_challenge': loginChallenge}),
      );

      if (response.statusCode == 200) {
@@ -377,7 +391,6 @@ class AuthProxyService {
          errorBody['error'] ??
              tr(
                'err.userfront.auth_proxy.oidc_accept',
-                fallback: 'OIDC 로그인 승인에 실패했습니다.',
              ),
        );
      }
@@ -386,8 +399,10 @@ class AuthProxyService {
    }
  }

-
-  static Future<Map<String, dynamic>> initiatePasswordReset(String loginId, {bool? drySend}) async {
+  static Future<Map<String, dynamic>> initiatePasswordReset(
+    String loginId, {
+    bool? drySend,
+  }) async {
    final url = Uri.parse('$_baseUrl/api/v1/auth/password/reset/initiate');
    final response = await http.post(
      url,
@@ -406,7 +421,6 @@ class AuthProxyService {
        errorBody['error'] ??
            tr(
              'err.userfront.auth_proxy.password_reset_init',
-              fallback: '비밀번호 재설정을 시작하지 못했습니다.',
            ),
      );
    }
@@ -424,7 +438,9 @@ class AuthProxyService {
    if (token != null && token.isNotEmpty) {
      query['token'] = token;
    }
-    final url = Uri.parse('$_baseUrl/api/v1/auth/password/reset/complete').replace(queryParameters: query);
+    final url = Uri.parse(
+      '$_baseUrl/api/v1/auth/password/reset/complete',
+    ).replace(queryParameters: query);
    final response = await http.post(
      url,
      headers: {'Content-Type': 'application/json'},
@@ -439,7 +455,6 @@ class AuthProxyService {
        errorBody['error'] ??
            tr(
              'err.userfront.auth_proxy.password_reset_complete',
-              fallback: '비밀번호 재설정에 실패했습니다.',
            ),
      );
    }
@@ -447,13 +462,11 @@ class AuthProxyService {

  static Future<void> sendSms(String phoneNumber) async {
    final url = Uri.parse('$_baseUrl/api/v1/auth/sms');
-    
+
    final response = await http.post(
      url,
      headers: {'Content-Type': 'application/json'},
-      body: jsonEncode({
-        'phoneNumber': phoneNumber,
-      }),
+      body: jsonEncode({'phoneNumber': phoneNumber}),
    );

    if (response.statusCode != 200) {
@@ -465,16 +478,16 @@ class AuthProxyService {
    }
  }

-  static Future<Map<String, dynamic>> verifySmsCode(String phoneNumber, String code) async {
+  static Future<Map<String, dynamic>> verifySmsCode(
+    String phoneNumber,
+    String code,
+  ) async {
    final url = Uri.parse('$_baseUrl/api/v1/auth/verify-sms');
-    
+
    final response = await http.post(
      url,
      headers: {'Content-Type': 'application/json'},
-      body: jsonEncode({
-        'phoneNumber': phoneNumber,
-        'code': code,
-      }),
+      body: jsonEncode({'phoneNumber': phoneNumber, 'code': code}),
    );

    if (response.statusCode == 200) {
@@ -532,10 +545,10 @@ class AuthProxyService {
    String? token,
    bool withCredentials = false,
  }) async {
-    final url = Uri.parse('$_baseUrl/api/v1/auth/qr/approve'); // Mapping to ScanQRLogin on backend
-    final payload = <String, dynamic>{
-      'pendingRef': pendingRef,
-    };
+    final url = Uri.parse(
+      '$_baseUrl/api/v1/auth/qr/approve',
+    ); // Mapping to ScanQRLogin on backend
+    final payload = <String, dynamic>{'pendingRef': pendingRef};
    if (token != null && token.isNotEmpty) {
      payload['token'] = token;
    }
@@ -593,7 +606,7 @@ class AuthProxyService {
    String? displayName,
  }) async {
    final url = Uri.parse('$_baseUrl/api/v1/admin/users');
-    
+
    final response = await http.post(
      url,
      headers: {
@@ -617,7 +630,10 @@ class AuthProxyService {
    }
  }

-  static Future<List<dynamic>> listUsers(String adminPassword, {String? query}) async {
+  static Future<List<dynamic>> listUsers(
+    String adminPassword, {
+    String? query,
+  }) async {
    var uri = Uri.parse('$_baseUrl/api/v1/admin/users');
    if (query != null && query.isNotEmpty) {
      uri = uri.replace(queryParameters: {'text': query});
@@ -646,7 +662,7 @@ class AuthProxyService {
  static Future<void> deleteUser(String adminPassword, String loginId) async {
    final encodedId = Uri.encodeComponent(loginId);
    final url = Uri.parse('$_baseUrl/api/v1/admin/users/$encodedId');
-    
+
    final response = await http.delete(
      url,
      headers: {
@@ -664,10 +680,14 @@ class AuthProxyService {
    }
  }

-  static Future<void> updateUserStatus(String adminPassword, String loginId, String status) async {
+  static Future<void> updateUserStatus(
+    String adminPassword,
+    String loginId,
+    String status,
+  ) async {
    final encodedId = Uri.encodeComponent(loginId);
    final url = Uri.parse('$_baseUrl/api/v1/admin/users/$encodedId/status');
-    
+
    final response = await http.patch(
      url,
      headers: {
@@ -695,7 +715,7 @@ class AuthProxyService {
  }) async {
    final encodedId = Uri.encodeComponent(loginId);
    final url = Uri.parse('$_baseUrl/api/v1/admin/users/$encodedId');
-    
+
    final body = <String, dynamic>{};
    if (email != null) body['email'] = email;
    if (phone != null) body['phone'] = phone;
@@ -725,18 +745,13 @@ class AuthProxyService {
    final token = AuthTokenStore.getToken();

    final client = createHttpClient(withCredentials: useCookie);
-    final headers = <String, String>{
-      'Content-Type': 'application/json',
-    };
+    final headers = <String, String>{'Content-Type': 'application/json'};
    if (!useCookie && token != null) {
      headers['Authorization'] = 'Bearer $token';
    }

    try {
-      final response = await client.get(
-        url,
-        headers: headers,
-      );
+      final response = await client.get(url, headers: headers);

      if (response.statusCode == 200) {
        final data = jsonDecode(response.body);
@@ -758,18 +773,13 @@ class AuthProxyService {
    final token = AuthTokenStore.getToken();

    final client = createHttpClient(withCredentials: useCookie);
-    final headers = <String, String>{
-      'Content-Type': 'application/json',
-    };
+    final headers = <String, String>{'Content-Type': 'application/json'};
    if (!useCookie && token != null) {
      headers['Authorization'] = 'Bearer $token';
    }

    try {
-      final response = await client.delete(
-        url,
-        headers: headers,
-      );
+      final response = await client.delete(url, headers: headers);

      if (response.statusCode != 200) {
        final errorBody = jsonDecode(response.body);
@@ -777,7 +787,6 @@ class AuthProxyService {
          errorBody['error'] ??
              tr(
                'err.userfront.auth_proxy.linked_app_revoke',
-                fallback: '연동 해지에 실패했습니다.',
              ),
        );
      }
@@ -786,7 +795,11 @@ class AuthProxyService {
    }
  }

-  static Future<void> sendLog(String level, String message, {Map<String, dynamic>? data}) async {
+  static Future<void> sendLog(
+    String level,
+    String message, {
+    Map<String, dynamic>? data,
+  }) async {
    if (!_canSendClientLog()) {
      return;
    }
@@ -808,11 +821,15 @@ class AuthProxyService {
    }
  }

-  static Future<void> logError(String message, {dynamic error, StackTrace? stackTrace}) async {
+  static Future<void> logError(
+    String message, {
+    dynamic error,
+    StackTrace? stackTrace,
+  }) async {
    final data = <String, dynamic>{};
    if (error != null) data['error'] = error.toString();
    if (stackTrace != null) data['stack'] = stackTrace.toString();
-    
+
    await sendLog('ERROR', message, data: data);
  }

@@ -861,7 +878,7 @@ class AuthProxyService {
  static Future<void> sendSignupCode(String target, String type) async {
    final path = type == 'email' ? 'send-email-code' : 'send-sms-code';
    final url = Uri.parse('$_baseUrl/api/v1/auth/signup/$path');
-    
+
    final response = await http.post(
      url,
      headers: {'Content-Type': 'application/json'},
@@ -877,17 +894,17 @@ class AuthProxyService {
    }
  }

-  static Future<bool> verifySignupCode(String target, String type, String code) async {
+  static Future<bool> verifySignupCode(
+    String target,
+    String type,
+    String code,
+  ) async {
    final url = Uri.parse('$_baseUrl/api/v1/auth/signup/verify-code');
-    
+
    final response = await http.post(
      url,
      headers: {'Content-Type': 'application/json'},
-      body: jsonEncode({
-        'target': target,
-        'type': type,
-        'code': code,
-      }),
+      body: jsonEncode({'target': target, 'type': type, 'code': code}),
    );

    if (response.statusCode == 200) {
@@ -908,7 +925,7 @@ class AuthProxyService {
    required bool termsAccepted,
  }) async {
    final url = Uri.parse('$_baseUrl/api/v1/auth/signup');
-    
+
    final response = await http.post(
      url,
      headers: {'Content-Type': 'application/json'},
--- a/userfront/lib/core/services/web_window_stub.dart
+++ b/userfront/lib/core/services/web_window_stub.dart
@@ -1,4 +1,6 @@
 class WebWindow {
+  void setTitle(String title) {}
+
  void redirectTo(String url) {}

  void alert(String message) {}
--- a/userfront/lib/core/services/web_window_web.dart
+++ b/userfront/lib/core/services/web_window_web.dart
@@ -3,6 +3,10 @@
 import 'dart:html' as html;

 class WebWindow {
+  void setTitle(String title) {
+    html.document.title = title;
+  }
+
  void redirectTo(String url) {
    html.window.location.href = url;
  }
--- a/userfront/lib/core/widgets/language_selector.dart
+++ b/userfront/lib/core/widgets/language_selector.dart
@@ -0,0 +1,65 @@
+import 'package:easy_localization/easy_localization.dart' hide tr;
+import 'package:flutter/material.dart';
+import 'package:go_router/go_router.dart';
+import 'package:userfront/i18n.dart';
+
+import '../i18n/locale_storage.dart';
+import '../i18n/locale_utils.dart';
+
+class LanguageSelector extends StatelessWidget {
+  const LanguageSelector({super.key, this.compact = false});
+
+  final bool compact;
+
+  @override
+  Widget build(BuildContext context) {
+    final current = context.locale.languageCode;
+    final items = [
+      DropdownMenuItem(
+        value: 'ko',
+        child: Text(tr('ui.common.language_ko')),
+      ),
+      DropdownMenuItem(
+        value: 'en',
+        child: Text(tr('ui.common.language_en', fallback: 'English')),
+      ),
+    ];
+
+    final iconSize = compact ? 16.0 : 18.0;
+    final dropdown = DropdownButtonHideUnderline(
+      child: DropdownButton<String>(
+        value: current,
+        items: items,
+        isDense: true,
+        icon: Icon(Icons.arrow_drop_down, size: compact ? 18 : 20),
+        onChanged: (value) async {
+          if (value == null || value == current) {
+            return;
+          }
+          LocaleStorage.write(value);
+          await context.setLocale(Locale(value));
+          final uri = GoRouterState.of(context).uri;
+          final target = buildLocalizedPath(value, uri);
+          if (context.mounted) {
+            context.go(target);
+          }
+        },
+      ),
+    );
+
+    return Padding(
+      padding: EdgeInsets.only(top: compact ? 0 : 2),
+      child: ConstrainedBox(
+        constraints: BoxConstraints(minHeight: compact ? 24 : 28),
+        child: Row(
+          mainAxisSize: MainAxisSize.min,
+          children: [
+            Icon(Icons.language, size: iconSize),
+            const SizedBox(width: 6),
+            dropdown,
+          ],
+        ),
+      ),
+    );
+  }
+}
--- a/userfront/lib/features/auth/presentation/error_screen.dart
+++ b/userfront/lib/features/auth/presentation/error_screen.dart
@@ -30,32 +30,33 @@ class ErrorScreen extends StatelessWidget {
        ? (isWhitelisted && hasCode ? normalizedCode : 'unknown_error')
        : (hasCode ? normalizedCode : 'unknown_error');
    final title = isProd
-        ? tr('msg.userfront.error.title', fallback: '인증 과정에서 오류가 발생했습니다')
+        ? tr('msg.userfront.error.title')
        : (hasCode
-            ? tr(
-                'msg.userfront.error.title_with_code',
-                fallback: '오류: {{code}}',
-                params: {'code': normalizedCode},
-              )
-            : tr('msg.userfront.error.title_generic', fallback: '오류가 발생했습니다'));
+              ? tr(
+                  'msg.userfront.error.title_with_code',
+                  params: {'code': normalizedCode},
+                )
+              : tr(
+                  'msg.userfront.error.title_generic',
+                ));
    final detail = isProd
        ? (isWhitelisted
-            ? tr(
-                'msg.userfront.error.whitelist.$normalizedCode',
-                fallback: whitelistFallback,
-              )
-            : tr(
-                'msg.userfront.error.detail_contact',
-                fallback: '에러가 계속되면 관리자에게 문의해주세요',
-              ))
+              ? tr(
+                  'msg.userfront.error.whitelist.$normalizedCode',
+                  fallback: whitelistFallback,
+                )
+              : tr(
+                  'msg.userfront.error.detail_contact',
+                ))
        : ((description?.isNotEmpty == true)
-            ? description!
-            : (hasCode
-                ? tr('msg.userfront.error.detail_generic', fallback: '오류가 발생했습니다.')
-                : tr(
-                    'msg.userfront.error.detail_request',
-                    fallback: '요청을 처리하는 중 문제가 발생했습니다.',
-                  )));
+              ? description!
+              : (hasCode
+                    ? tr(
+                        'msg.userfront.error.detail_generic',
+                      )
+                    : tr(
+                        'msg.userfront.error.detail_request',
+                      )));

    return Scaffold(
      backgroundColor: const Color(0xFFF7F8FA),
@@ -94,7 +95,6 @@ class ErrorScreen extends StatelessWidget {
                  Text(
                    tr(
                      'msg.userfront.error.type',
-                      fallback: '오류 종류: {{type}}',
                      params: {'type': errorType},
                    ),
                    style: theme.textTheme.bodySmall?.copyWith(
@@ -106,7 +106,6 @@ class ErrorScreen extends StatelessWidget {
                    Text(
                      tr(
                        'msg.userfront.error.id',
-                        fallback: '오류 ID: {{id}}',
                        params: {'id': errorId!},
                      ),
                      style: theme.textTheme.bodySmall?.copyWith(
@@ -124,27 +123,35 @@ class ErrorScreen extends StatelessWidget {
                        style: ElevatedButton.styleFrom(
                          backgroundColor: const Color(0xFF111827),
                          foregroundColor: Colors.white,
-                          padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 12),
+                          padding: const EdgeInsets.symmetric(
+                            horizontal: 16,
+                            vertical: 12,
+                          ),
                          shape: RoundedRectangleBorder(
                            borderRadius: BorderRadius.circular(10),
                          ),
                        ),
                        child: Text(
-                          tr('ui.userfront.error.go_login', fallback: '로그인으로 이동'),
+                          tr(
+                            'ui.userfront.error.go_login',
+                          ),
                        ),
                      ),
                      OutlinedButton(
                        onPressed: () => context.go('/'),
                        style: OutlinedButton.styleFrom(
                          foregroundColor: const Color(0xFF111827),
-                          padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 12),
+                          padding: const EdgeInsets.symmetric(
+                            horizontal: 16,
+                            vertical: 12,
+                          ),
                          side: const BorderSide(color: Color(0xFFCBD5F5)),
                          shape: RoundedRectangleBorder(
                            borderRadius: BorderRadius.circular(10),
                          ),
                        ),
                        child: Text(
-                          tr('ui.userfront.error.go_home', fallback: '홈으로 이동'),
+                          tr('ui.userfront.error.go_home'),
                        ),
                      ),
                    ],
--- a/userfront/lib/features/auth/presentation/forgot_password_screen.dart
+++ b/userfront/lib/features/auth/presentation/forgot_password_screen.dart
@@ -17,7 +17,9 @@ class _ForgotPasswordScreenState extends State<ForgotPasswordScreen> {
  @override
  void initState() {
    super.initState();
-    _drySendEnabled = _parseBoolParam(Uri.base.queryParameters['drySend']) && !AuthProxyService.isProdEnv;
+    _drySendEnabled =
+        _parseBoolParam(Uri.base.queryParameters['drySend']) &&
+        !AuthProxyService.isProdEnv;
  }

  Future<void> _handlePasswordReset() async {
@@ -26,7 +28,6 @@ class _ForgotPasswordScreenState extends State<ForgotPasswordScreen> {
      _showError(
        tr(
          'msg.userfront.forgot.input_required',
-          fallback: '이메일 또는 휴대폰 번호를 입력해주세요.',
        ),
      );
      return;
@@ -44,14 +45,16 @@ class _ForgotPasswordScreenState extends State<ForgotPasswordScreen> {
    setState(() => _isLoading = true);

    try {
-      await AuthProxyService.initiatePasswordReset(loginId, drySend: _drySendEnabled);
+      await AuthProxyService.initiatePasswordReset(
+        loginId,
+        drySend: _drySendEnabled,
+      );
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(
            content: Text(
              tr(
                'msg.userfront.forgot.sent',
-                fallback: '비밀번호 재설정 링크가 전송되었습니다. 이메일 또는 SMS를 확인해주세요.',
              ),
            ),
            backgroundColor: Colors.green,
@@ -64,7 +67,6 @@ class _ForgotPasswordScreenState extends State<ForgotPasswordScreen> {
        _showError(
          tr(
            'msg.userfront.forgot.error',
-            fallback: '전송에 실패했습니다: {{error}}',
            params: {'error': e.toString()},
          ),
        );
@@ -94,7 +96,7 @@ class _ForgotPasswordScreenState extends State<ForgotPasswordScreen> {
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
-        title: Text(tr('ui.userfront.forgot.title', fallback: '비밀번호 재설정')),
+        title: Text(tr('ui.userfront.forgot.title')),
        centerTitle: true,
      ),
      body: Center(
@@ -106,17 +108,17 @@ class _ForgotPasswordScreenState extends State<ForgotPasswordScreen> {
            crossAxisAlignment: CrossAxisAlignment.stretch,
            children: [
              Text(
-                tr('ui.userfront.forgot.heading', fallback: '비밀번호를 잊으셨나요?'),
-                style: TextStyle(
-                  fontSize: 28,
-                  fontWeight: FontWeight.bold,
-                ),
+                tr('ui.userfront.forgot.heading'),
+                style: TextStyle(fontSize: 28, fontWeight: FontWeight.bold),
                textAlign: TextAlign.center,
              ),
              if (_drySendEnabled) ...[
                const SizedBox(height: 12),
                Container(
-                  padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 10),
+                  padding: const EdgeInsets.symmetric(
+                    horizontal: 12,
+                    vertical: 10,
+                  ),
                  decoration: BoxDecoration(
                    color: const Color(0xFFFFF3CD),
                    borderRadius: BorderRadius.circular(8),
@@ -124,15 +126,20 @@ class _ForgotPasswordScreenState extends State<ForgotPasswordScreen> {
                  ),
                  child: Row(
                    children: [
-                      const Icon(Icons.warning_amber_rounded, color: Color(0xFF8A6D3B)),
+                      const Icon(
+                        Icons.warning_amber_rounded,
+                        color: Color(0xFF8A6D3B),
+                      ),
                      const SizedBox(width: 8),
                      Expanded(
                        child: Text(
                          tr(
                            'msg.userfront.forgot.dry_send',
-                            fallback: 'drySend 모드: 실제 이메일/SMS는 발송되지 않습니다.',
                          ),
-                          style: const TextStyle(color: Color(0xFF8A6D3B), fontSize: 12),
+                          style: const TextStyle(
+                            color: Color(0xFF8A6D3B),
+                            fontSize: 12,
+                          ),
                        ),
                      ),
                    ],
@@ -143,8 +150,6 @@ class _ForgotPasswordScreenState extends State<ForgotPasswordScreen> {
              Text(
                tr(
                  'msg.userfront.forgot.description',
-                  fallback:
-                      '계정과 연결된 이메일 주소 또는 휴대폰 번호를 입력하시면, 비밀번호를 재설정할 수 있는 링크를 보내드립니다.',
                ),
                textAlign: TextAlign.center,
                style: const TextStyle(color: Colors.grey),
@@ -155,7 +160,6 @@ class _ForgotPasswordScreenState extends State<ForgotPasswordScreen> {
                decoration: InputDecoration(
                  labelText: tr(
                    'ui.userfront.forgot.input_label',
-                    fallback: '이메일 또는 휴대폰 번호',
                  ),
                  border: const OutlineInputBorder(),
                  prefixIcon: const Icon(Icons.person_outline),
@@ -172,13 +176,13 @@ class _ForgotPasswordScreenState extends State<ForgotPasswordScreen> {
                    ? const SizedBox(
                        height: 20,
                        width: 20,
-                        child: CircularProgressIndicator(strokeWidth: 2, color: Colors.white),
+                        child: CircularProgressIndicator(
+                          strokeWidth: 2,
+                          color: Colors.white,
+                        ),
                      )
                    : Text(
-                        tr(
-                          'ui.userfront.forgot.submit',
-                          fallback: '재설정 링크 전송',
-                        ),
+                        tr('ui.userfront.forgot.submit'),
                      ),
              ),
            ],
--- a/userfront/lib/features/auth/presentation/login_screen.dart
+++ b/userfront/lib/features/auth/presentation/login_screen.dart
--- a/userfront/lib/features/auth/presentation/login_success_screen.dart
+++ b/userfront/lib/features/auth/presentation/login_success_screen.dart
@@ -14,23 +14,26 @@ class LoginSuccessScreen extends StatelessWidget {
          child: Column(
            mainAxisAlignment: MainAxisAlignment.center,
            children: [
-              const Icon(Icons.check_circle_outline, size: 80, color: Colors.green),
+              const Icon(
+                Icons.check_circle_outline,
+                size: 80,
+                color: Colors.green,
+              ),
              const SizedBox(height: 24),
              Text(
-                tr('ui.userfront.login_success.title', fallback: '로그인 완료'),
-                style: TextStyle(
-                  fontSize: 32,
-                  fontWeight: FontWeight.bold,
-                ),
+                tr('ui.userfront.login_success.title'),
+                style: TextStyle(fontSize: 32, fontWeight: FontWeight.bold),
              ),
              const SizedBox(height: 16),
              Text(
-                tr('msg.userfront.login_success.subtitle', fallback: '성공적으로 로그인되었습니다.'),
+                tr(
+                  'msg.userfront.login_success.subtitle',
+                ),
                textAlign: TextAlign.center,
                style: const TextStyle(color: Colors.grey, fontSize: 16),
              ),
              const SizedBox(height: 48),
-              
+
              // 이 버튼이 QR 카메라를 켜는 버튼입니다.
              FilledButton.icon(
                onPressed: () {
@@ -38,12 +41,17 @@ class LoginSuccessScreen extends StatelessWidget {
                },
                icon: const Icon(Icons.camera_alt, size: 28),
                label: Text(
-                  tr('ui.userfront.login_success.qr', fallback: 'QR 인증 (카메라 켜기)'),
+                  tr(
+                    'ui.userfront.login_success.qr',
+                  ),
                ),
                style: FilledButton.styleFrom(
                  minimumSize: const Size.fromHeight(80), // 버튼 높이를 더 크게
                  backgroundColor: Colors.blue.shade700,
-                  textStyle: const TextStyle(fontSize: 20, fontWeight: FontWeight.bold),
+                  textStyle: const TextStyle(
+                    fontSize: 20,
+                    fontWeight: FontWeight.bold,
+                  ),
                  shape: RoundedRectangleBorder(
                    borderRadius: BorderRadius.circular(16),
                  ),
@@ -57,7 +65,6 @@ class LoginSuccessScreen extends StatelessWidget {
                child: Text(
                  tr(
                    'ui.userfront.login_success.later',
-                    fallback: '나중에 하기 (대시보드로 이동)',
                  ),
                  style: const TextStyle(color: Colors.grey),
                ),
--- a/userfront/lib/features/auth/presentation/qr_scan_screen.dart
+++ b/userfront/lib/features/auth/presentation/qr_scan_screen.dart
@@ -87,7 +87,7 @@ class _QRScanScreenState extends State<QRScanScreen> {

  Future<void> _onDetect(BarcodeCapture capture) async {
    if (_isScanned) return;
-    
+
    final List<Barcode> barcodes = capture.barcodes;
    for (final barcode in barcodes) {
      if (barcode.rawValue != null) {
@@ -119,7 +119,7 @@ class _QRScanScreenState extends State<QRScanScreen> {

        _log.info('QR Code detected raw: $qrData, ref: $pendingRef');
        final approveRef = qrData;
-        
+
        final storedToken = AuthTokenStore.getToken();
        final sessionToken = storedToken;
        var usesCookie = AuthTokenStore.usesCookie();
@@ -140,13 +140,12 @@ class _QRScanScreenState extends State<QRScanScreen> {
            token: sessionToken,
            withCredentials: usesCookie,
          );
-          
+
          if (mounted) {
            setState(() {
              _isSuccess = true;
              _resultMessage = tr(
                'msg.userfront.qr.approve_success',
-                fallback: 'QR 승인 완료! PC 화면에서 로그인이 진행됩니다.',
              );
              _isProcessing = false;
            });
@@ -158,7 +157,6 @@ class _QRScanScreenState extends State<QRScanScreen> {
              _isSuccess = false;
              _resultMessage = tr(
                'msg.userfront.qr.approve_error',
-                fallback: 'QR 승인 실패: {{error}}',
                params: {'error': '$e'},
              );
              _isProcessing = false;
@@ -193,7 +191,6 @@ class _QRScanScreenState extends State<QRScanScreen> {
            content: Text(
              tr(
                'msg.userfront.qr.permission_error',
-                fallback: '카메라 권한 요청에 실패했습니다. 브라우저/OS 설정을 확인해주세요.',
              ),
            ),
            backgroundColor: Colors.red,
@@ -212,8 +209,8 @@ class _QRScanScreenState extends State<QRScanScreen> {
    final icon = success ? Icons.check_circle_outline : Icons.error_outline;
    final color = success ? Colors.green : Colors.red;
    final title = success
-        ? tr('ui.userfront.qr.result_success', fallback: '승인 완료')
-        : tr('ui.userfront.qr.result_failure', fallback: '승인 실패');
+        ? tr('ui.userfront.qr.result_success')
+        : tr('ui.userfront.qr.result_failure');
    final message = _resultMessage ?? '';

    return Center(
@@ -226,7 +223,11 @@ class _QRScanScreenState extends State<QRScanScreen> {
            const SizedBox(height: 16),
            Text(
              title,
-              style: TextStyle(fontSize: 22, fontWeight: FontWeight.bold, color: color),
+              style: TextStyle(
+                fontSize: 22,
+                fontWeight: FontWeight.bold,
+                color: color,
+              ),
            ),
            const SizedBox(height: 12),
            Text(
@@ -238,12 +239,12 @@ class _QRScanScreenState extends State<QRScanScreen> {
            if (!success)
              FilledButton(
                onPressed: _resetScan,
-                child: Text(tr('ui.userfront.qr.rescan', fallback: '다시 스캔')),
+                child: Text(tr('ui.userfront.qr.rescan')),
              ),
            if (success)
              FilledButton(
                onPressed: () => context.pop(),
-                child: Text(tr('ui.common.close', fallback: '닫기')),
+                child: Text(tr('ui.common.close')),
              ),
          ],
        ),
@@ -268,7 +269,8 @@ class _QRScanScreenState extends State<QRScanScreen> {
                  controller: controller,
                  onDetect: _onDetect,
                  errorBuilder: (context, error) {
-                    final isPermissionDenied = error.errorCode ==
+                    final isPermissionDenied =
+                        error.errorCode ==
                        MobileScannerErrorCode.permissionDenied;
                    return Center(
                      child: Column(
@@ -280,11 +282,9 @@ class _QRScanScreenState extends State<QRScanScreen> {
                            isPermissionDenied
                                ? tr(
                                    'msg.userfront.qr.permission_required',
-                                    fallback: '카메라 권한이 필요합니다.',
                                  )
                                : tr(
                                    'msg.userfront.qr.camera_error',
-                                    fallback: '카메라 오류: {{error}}',
                                    params: {'error': '${error.errorCode}'},
                                  ),
                          ),
@@ -295,10 +295,11 @@ class _QRScanScreenState extends State<QRScanScreen> {
                                : _requestCameraPermission,
                            child: Text(
                              _isRequestingCamera
-                                  ? tr('ui.common.requesting', fallback: '요청 중...')
+                                  ? tr(
+                                      'ui.common.requesting',
+                                    )
                                  : tr(
                                      'ui.userfront.qr.request_permission',
-                                      fallback: '카메라 권한 요청하기',
                                    ),
                            ),
                          ),
--- a/userfront/lib/features/auth/presentation/reset_password_screen.dart
+++ b/userfront/lib/features/auth/presentation/reset_password_screen.dart
@@ -13,7 +13,8 @@ class ResetPasswordScreen extends StatefulWidget {

 class _ResetPasswordScreenState extends State<ResetPasswordScreen> {
  final TextEditingController _passwordController = TextEditingController();
-  final TextEditingController _confirmPasswordController = TextEditingController();
+  final TextEditingController _confirmPasswordController =
+      TextEditingController();
  final _formKey = GlobalKey<FormState>();
  bool _isLoading = false;
  String? _loginId;
@@ -31,13 +32,13 @@ class _ResetPasswordScreenState extends State<ResetPasswordScreen> {

    // 2. Fallback to URI query parameter if not available via router
    if (_loginId == null || _loginId!.isEmpty) {
-    final uri = Uri.base;
-    _loginId = uri.queryParameters['loginId'];
-  }
+      final uri = Uri.base;
+      _loginId = uri.queryParameters['loginId'];
+    }

-  // 토큰도 함께 읽어놓는다.
-  final uri = Uri.base;
-  _token = uri.queryParameters['token'];
+    // 토큰도 함께 읽어놓는다.
+    final uri = Uri.base;
+    _token = uri.queryParameters['token'];

    _loadPolicy();
  }
@@ -66,11 +67,11 @@ class _ResetPasswordScreenState extends State<ResetPasswordScreen> {

  Future<void> _handlePasswordReset() async {
    if (_formKey.currentState?.validate() != true) return;
-    if ((_loginId == null || _loginId!.isEmpty) && (_token == null || _token!.isEmpty)) {
+    if ((_loginId == null || _loginId!.isEmpty) &&
+        (_token == null || _token!.isEmpty)) {
      _showError(
        tr(
          'msg.userfront.reset.invalid_link',
-          fallback: '유효하지 않은 재설정 링크입니다. (loginId/token 누락)',
        ),
      );
      return;
@@ -91,7 +92,6 @@ class _ResetPasswordScreenState extends State<ResetPasswordScreen> {
            content: Text(
              tr(
                'msg.userfront.reset.success',
-                fallback: '비밀번호가 성공적으로 변경되었습니다. 다시 로그인해주세요.',
              ),
            ),
            backgroundColor: Colors.green,
@@ -104,7 +104,6 @@ class _ResetPasswordScreenState extends State<ResetPasswordScreen> {
        _showError(
          tr(
            'msg.userfront.reset.error.generic',
-            fallback: '비밀번호 변경에 실패했습니다: {{error}}',
            params: {'error': e.toString()},
          ),
        );
@@ -126,7 +125,6 @@ class _ResetPasswordScreenState extends State<ResetPasswordScreen> {
    if (_isPolicyLoading) {
      return tr(
        'msg.userfront.reset.policy_loading',
-        fallback: '비밀번호 정책을 불러오는 중입니다...',
      );
    }
    final minLength = (_policy?['minLength'] as int?) ?? 12;
@@ -139,7 +137,6 @@ class _ResetPasswordScreenState extends State<ResetPasswordScreen> {
    final parts = <String>[
      tr(
        'msg.userfront.reset.policy.min_length',
-        fallback: '최소 {{count}}자 이상',
        params: {'count': '$minLength'},
      ),
    ];
@@ -147,29 +144,26 @@ class _ResetPasswordScreenState extends State<ResetPasswordScreen> {
      parts.add(
        tr(
          'msg.userfront.reset.policy.min_types',
-          fallback: '영문 대/소문자/숫자/특수문자 중 {{count}}가지 이상',
          params: {'count': '$minTypes'},
        ),
      );
    }
    if (requiresLower) {
      parts.add(
-        tr('msg.userfront.reset.policy.lowercase', fallback: '소문자 1개 이상'),
+        tr('msg.userfront.reset.policy.lowercase'),
      );
    }
    if (requiresUpper) {
      parts.add(
-        tr('msg.userfront.reset.policy.uppercase', fallback: '대문자 1개 이상'),
+        tr('msg.userfront.reset.policy.uppercase'),
      );
    }
    if (requiresNumber) {
-      parts.add(
-        tr('msg.userfront.reset.policy.number', fallback: '숫자 1개 이상'),
-      );
+      parts.add(tr('msg.userfront.reset.policy.number'));
    }
    if (requiresSymbol) {
      parts.add(
-        tr('msg.userfront.reset.policy.symbol', fallback: '특수문자 1개 이상'),
+        tr('msg.userfront.reset.policy.symbol'),
      );
    }

@@ -180,16 +174,16 @@ class _ResetPasswordScreenState extends State<ResetPasswordScreen> {
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
-        title: Text(
-          tr('ui.userfront.reset.title', fallback: '새 비밀번호 설정'),
-        ),
+        title: Text(tr('ui.userfront.reset.title')),
        centerTitle: true,
      ),
      body: Center(
        child: Container(
          constraints: const BoxConstraints(maxWidth: 400),
          padding: const EdgeInsets.all(24),
-          child: (_loginId == null || _loginId!.isEmpty) && (_token == null || _token!.isEmpty)
+          child:
+              (_loginId == null || _loginId!.isEmpty) &&
+                  (_token == null || _token!.isEmpty)
              ? _buildInvalidTokenView()
              : Form(
                  key: _formKey,
@@ -200,7 +194,6 @@ class _ResetPasswordScreenState extends State<ResetPasswordScreen> {
                      Text(
                        tr(
                          'ui.userfront.reset.subtitle',
-                          fallback: '새로운 비밀번호 설정',
                        ),
                        style: TextStyle(
                          fontSize: 28,
@@ -221,13 +214,14 @@ class _ResetPasswordScreenState extends State<ResetPasswordScreen> {
                        decoration: InputDecoration(
                          labelText: tr(
                            'ui.userfront.reset.new_password',
-                            fallback: '새 비밀번호',
                          ),
                          border: const OutlineInputBorder(),
                          prefixIcon: const Icon(Icons.lock_outline),
                          suffixIcon: IconButton(
                            icon: Icon(
-                              _isPasswordObscured ? Icons.visibility_off : Icons.visibility,
+                              _isPasswordObscured
+                                  ? Icons.visibility_off
+                                  : Icons.visibility,
                            ),
                            onPressed: () {
                              setState(() {
@@ -241,14 +235,13 @@ class _ResetPasswordScreenState extends State<ResetPasswordScreen> {
                          if (val.isEmpty) {
                            return tr(
                              'msg.userfront.reset.error.empty_password',
-                              fallback: '비밀번호를 입력해주세요.',
                            );
                          }
-                          final minLength = (_policy?['minLength'] as int?) ?? 12;
+                          final minLength =
+                              (_policy?['minLength'] as int?) ?? 12;
                          if (val.length < minLength) {
                            return tr(
                              'msg.userfront.reset.error.min_length',
-                              fallback: '비밀번호는 최소 {{count}}자 이상이어야 합니다.',
                              params: {'count': '$minLength'},
                            );
                          }
@@ -262,12 +255,11 @@ class _ResetPasswordScreenState extends State<ResetPasswordScreen> {
                          if (hasNumber) typeCount++;
                          if (hasSymbol) typeCount++;

-                          final minTypes = (_policy?['minCharacterTypes'] as int?) ?? 0;
+                          final minTypes =
+                              (_policy?['minCharacterTypes'] as int?) ?? 0;
                          if (minTypes > 0 && typeCount < minTypes) {
                            return tr(
                              'msg.userfront.reset.error.min_types',
-                              fallback:
-                                  '비밀번호는 영문 대/소문자/숫자/특수문자 중 {{count}}가지 이상 포함해야 합니다.',
                              params: {'count': '$minTypes'},
                            );
                          }
@@ -275,25 +267,22 @@ class _ResetPasswordScreenState extends State<ResetPasswordScreen> {
                          if ((_policy?['lowercase'] ?? true) && !hasLower) {
                            return tr(
                              'msg.userfront.reset.error.lowercase',
-                              fallback: '최소 1개 이상의 소문자를 포함해야 합니다.',
                            );
                          }
                          if ((_policy?['uppercase'] ?? false) && !hasUpper) {
                            return tr(
                              'msg.userfront.reset.error.uppercase',
-                              fallback: '최소 1개 이상의 대문자를 포함해야 합니다.',
                            );
                          }
                          if ((_policy?['number'] ?? true) && !hasNumber) {
                            return tr(
                              'msg.userfront.reset.error.number',
-                              fallback: '최소 1개 이상의 숫자를 포함해야 합니다.',
                            );
                          }
-                          if ((_policy?['nonAlphanumeric'] ?? true) && !hasSymbol) {
+                          if ((_policy?['nonAlphanumeric'] ?? true) &&
+                              !hasSymbol) {
                            return tr(
                              'msg.userfront.reset.error.symbol',
-                              fallback: '최소 1개 이상의 특수문자를 포함해야 합니다.',
                            );
                          }
                          return null;
@@ -306,17 +295,19 @@ class _ResetPasswordScreenState extends State<ResetPasswordScreen> {
                        decoration: InputDecoration(
                          labelText: tr(
                            'ui.userfront.reset.confirm_password',
-                            fallback: '새 비밀번호 확인',
                          ),
                          border: const OutlineInputBorder(),
                          prefixIcon: const Icon(Icons.lock_outline),
                          suffixIcon: IconButton(
                            icon: Icon(
-                              _isConfirmPasswordObscured ? Icons.visibility_off : Icons.visibility,
+                              _isConfirmPasswordObscured
+                                  ? Icons.visibility_off
+                                  : Icons.visibility,
                            ),
                            onPressed: () {
                              setState(() {
-                                _isConfirmPasswordObscured = !_isConfirmPasswordObscured;
+                                _isConfirmPasswordObscured =
+                                    !_isConfirmPasswordObscured;
                              });
                            },
                          ),
@@ -325,7 +316,6 @@ class _ResetPasswordScreenState extends State<ResetPasswordScreen> {
                          if (value != _passwordController.text) {
                            return tr(
                              'msg.userfront.reset.error.mismatch',
-                              fallback: '비밀번호가 일치하지 않습니다.',
                            );
                          }
                          return null;
@@ -349,7 +339,6 @@ class _ResetPasswordScreenState extends State<ResetPasswordScreen> {
                            : Text(
                                tr(
                                  'ui.userfront.reset.submit',
-                                  fallback: '비밀번호 변경',
                                ),
                              ),
                      ),
@@ -369,8 +358,7 @@ class _ResetPasswordScreenState extends State<ResetPasswordScreen> {
          const Icon(Icons.error_outline, color: Colors.red, size: 60),
          const SizedBox(height: 16),
          Text(
-            tr('msg.userfront.reset.invalid_title',
-                fallback: '유효하지 않은 링크입니다.'),
+            tr('msg.userfront.reset.invalid_title'),
            style: const TextStyle(fontSize: 18, fontWeight: FontWeight.bold),
            textAlign: TextAlign.center,
          ),
@@ -378,7 +366,6 @@ class _ResetPasswordScreenState extends State<ResetPasswordScreen> {
          Text(
            tr(
              'msg.userfront.reset.invalid_body',
-              fallback: '비밀번호 재설정 링크가 만료되었거나 잘못되었습니다. 다시 시도해주세요.',
            ),
            textAlign: TextAlign.center,
          ),
--- a/userfront/lib/features/auth/presentation/signup_screen.dart
+++ b/userfront/lib/features/auth/presentation/signup_screen.dart
@@ -164,30 +164,36 @@ class _SignupScreenState extends State<SignupScreen> {
    final email = _emailController.text.trim();
    final emailRegex = RegExp(r'^[\w-\.]+@([\w-]+\.)+[\w-]{2,4}$');
    if (!emailRegex.hasMatch(email)) {
-      setState(() => _emailError = tr(
-            'msg.userfront.signup.email.invalid',
-            fallback: '유효한 이메일 형식이 아닙니다.',
-          ));
+      setState(
+        () => _emailError = tr(
+          'msg.userfront.signup.email.invalid',
+        ),
+      );
      return;
    }
-    setState(() { _isLoading = true; _emailError = null; });
+    setState(() {
+      _isLoading = true;
+      _emailError = null;
+    });
    try {
      final available = await AuthProxyService.checkEmailAvailability(email);
      if (!available) {
-        setState(() => _emailError = tr(
-              'msg.userfront.signup.email.duplicate',
-              fallback: '이미 가입된 이메일입니다.',
-            ));
+        setState(
+          () => _emailError = tr(
+            'msg.userfront.signup.email.duplicate',
+          ),
+        );
        return;
      }
      await AuthProxyService.sendSignupCode(email, 'email');
      _startTimer('email');
    } catch (e) {
-      setState(() => _emailError = tr(
-            'msg.userfront.signup.email.send_failed',
-            fallback: '발송 실패: {{error}}',
-            params: {'error': e.toString()},
-          ));
+      setState(
+        () => _emailError = tr(
+          'msg.userfront.signup.email.send_failed',
+          params: {'error': e.toString()},
+        ),
+      );
    } finally {
      setState(() => _isLoading = false);
    }
@@ -197,7 +203,11 @@ class _SignupScreenState extends State<SignupScreen> {
    final code = _emailCodeController.text.trim();
    if (code.length != 6) return;
    try {
-      final success = await AuthProxyService.verifySignupCode(_emailController.text.trim(), 'email', code);
+      final success = await AuthProxyService.verifySignupCode(
+        _emailController.text.trim(),
+        'email',
+        code,
+      );
      if (success) {
        setState(() {
          _isEmailVerified = true;
@@ -206,33 +216,39 @@ class _SignupScreenState extends State<SignupScreen> {
          _emailError = null;
        });
      } else {
-        setState(() => _emailError = tr(
-              'msg.userfront.signup.email.code_mismatch',
-              fallback: '인증코드가 일치하지 않습니다.',
-            ));
+        setState(
+          () => _emailError = tr(
+            'msg.userfront.signup.email.code_mismatch',
+          ),
+        );
      }
    } catch (e) {
-      setState(() => _emailError = tr(
-            'msg.userfront.signup.email.verify_failed',
-            fallback: '인증 실패: {{error}}',
-            params: {'error': e.toString()},
-          ));
+      setState(
+        () => _emailError = tr(
+          'msg.userfront.signup.email.verify_failed',
+          params: {'error': e.toString()},
+        ),
+      );
    }
  }

  Future<void> _sendPhoneCode() async {
    final phone = _phoneController.text.trim();
    if (phone.isEmpty) return;
-    setState(() { _isLoading = true; _phoneError = null; });
+    setState(() {
+      _isLoading = true;
+      _phoneError = null;
+    });
    try {
      await AuthProxyService.sendSignupCode(phone, 'phone');
      _startTimer('phone');
    } catch (e) {
-      setState(() => _phoneError = tr(
-            'msg.userfront.signup.phone.send_failed',
-            fallback: '발송 실패: {{error}}',
-            params: {'error': e.toString()},
-          ));
+      setState(
+        () => _phoneError = tr(
+          'msg.userfront.signup.phone.send_failed',
+          params: {'error': e.toString()},
+        ),
+      );
    } finally {
      setState(() => _isLoading = false);
    }
@@ -242,7 +258,11 @@ class _SignupScreenState extends State<SignupScreen> {
    final code = _phoneCodeController.text.trim();
    if (code.length != 6) return;
    try {
-      final success = await AuthProxyService.verifySignupCode(_phoneController.text.trim(), 'phone', code);
+      final success = await AuthProxyService.verifySignupCode(
+        _phoneController.text.trim(),
+        'phone',
+        code,
+      );
      if (success) {
        setState(() {
          _isPhoneVerified = true;
@@ -251,26 +271,29 @@ class _SignupScreenState extends State<SignupScreen> {
          _phoneError = null;
        });
      } else {
-        setState(() => _phoneError = tr(
-              'msg.userfront.signup.phone.code_mismatch',
-              fallback: '인증코드가 일치하지 않습니다.',
-            ));
+        setState(
+          () => _phoneError = tr(
+            'msg.userfront.signup.phone.code_mismatch',
+          ),
+        );
      }
    } catch (e) {
-      setState(() => _phoneError = tr(
-            'msg.userfront.signup.phone.verify_failed',
-            fallback: '인증 실패: {{error}}',
-            params: {'error': e.toString()},
-          ));
+      setState(
+        () => _phoneError = tr(
+          'msg.userfront.signup.phone.verify_failed',
+          params: {'error': e.toString()},
+        ),
+      );
    }
  }

  Future<void> _handleSignup() async {
    if (_passwordController.text != _confirmPasswordController.text) {
-      setState(() => _confirmPasswordError = tr(
-            'msg.userfront.signup.password.mismatch',
-            fallback: '비밀번호가 일치하지 않습니다.',
-          ));
+      setState(
+        () => _confirmPasswordError = tr(
+          'msg.userfront.signup.password.mismatch',
+        ),
+      );
      return;
    }
    if (!_formKey.currentState!.validate()) return;
@@ -288,7 +311,9 @@ class _SignupScreenState extends State<SignupScreen> {
        phone: _phoneController.text.trim(),
        affiliationType: _affiliationType,
        companyCode: _affiliationType == 'AFFILIATE' ? _companyCode : null,
-        department: _deptController.text.trim().isEmpty ? (_affiliationType == 'GENERAL' ? 'External' : '') : _deptController.text.trim(),
+        department: _deptController.text.trim().isEmpty
+            ? (_affiliationType == 'GENERAL' ? 'External' : '')
+            : _deptController.text.trim(),
        termsAccepted: true,
      );
      if (mounted) _showSuccessDialog();
@@ -298,32 +323,26 @@ class _SignupScreenState extends State<SignupScreen> {
        if (eStr.contains('uppercase')) {
          _passwordError = tr(
            'msg.userfront.signup.password.uppercase_required',
-            fallback: '대문자가 최소 1개 이상 포함되어야 합니다.',
          );
        } else if (eStr.contains('lowercase')) {
          _passwordError = tr(
            'msg.userfront.signup.password.lowercase_required',
-            fallback: '소문자가 최소 1개 이상 포함되어야 합니다.',
          );
        } else if (eStr.contains('digit') || eStr.contains('number')) {
          _passwordError = tr(
            'msg.userfront.signup.password.number_required',
-            fallback: '숫자가 최소 1개 이상 포함되어야 합니다.',
          );
        } else if (eStr.contains('symbol') || eStr.contains('special')) {
          _passwordError = tr(
            'msg.userfront.signup.password.symbol_required',
-            fallback: '특수문자가 최소 1개 이상 포함되어야 합니다.',
          );
        } else if (eStr.contains('length') || eStr.contains('12 characters')) {
          _passwordError = tr(
            'msg.userfront.signup.password.length_required',
-            fallback: '비밀번호는 최소 12자 이상이어야 합니다.',
          );
        } else {
          _passwordError = tr(
            'msg.userfront.signup.failed',
-            fallback: '가입 실패: {{error}}',
            params: {'error': e.toString()},
          );
        }
@@ -339,16 +358,16 @@ class _SignupScreenState extends State<SignupScreen> {
      barrierDismissible: false,
      builder: (context) => AlertDialog(
        title: Text(
-          tr('msg.userfront.signup.success.title', fallback: '회원가입 완료'),
+          tr('msg.userfront.signup.success.title'),
        ),
        content: Text(
-          tr('msg.userfront.signup.success.body', fallback: '성공적으로 가입되었습니다.'),
+          tr('msg.userfront.signup.success.body'),
        ),
        actions: [
          TextButton(
            onPressed: () => context.go('/signin'),
            child: Text(
-              tr('ui.userfront.signup.success.action', fallback: '로그인하기'),
+              tr('ui.userfront.signup.success.action'),
            ),
          ),
        ],
@@ -365,22 +384,22 @@ class _SignupScreenState extends State<SignupScreen> {
        children: [
          _stepCircle(
            1,
-            tr('ui.userfront.signup.steps.agreement', fallback: '약관동의'),
+            tr('ui.userfront.signup.steps.agreement'),
          ),
          _stepLine(1),
          _stepCircle(
            2,
-            tr('ui.userfront.signup.steps.verify', fallback: '본인인증'),
+            tr('ui.userfront.signup.steps.verify'),
          ),
          _stepLine(2),
          _stepCircle(
            3,
-            tr('ui.userfront.signup.steps.profile', fallback: '정보입력'),
+            tr('ui.userfront.signup.steps.profile'),
          ),
          _stepLine(3),
          _stepCircle(
            4,
-            tr('ui.userfront.signup.steps.password', fallback: '비밀번호'),
+            tr('ui.userfront.signup.steps.password'),
          ),
        ],
      ),
@@ -394,11 +413,28 @@ class _SignupScreenState extends State<SignupScreen> {
      children: [
        CircleAvatar(
          radius: 12,
-          backgroundColor: isDone ? Colors.green : (isCurrent ? Colors.black : Colors.grey[300]),
-          child: isDone ? const Icon(Icons.check, size: 14, color: Colors.white) : Text('$step', style: TextStyle(color: isCurrent ? Colors.white : Colors.black54, fontSize: 10)),
+          backgroundColor: isDone
+              ? Colors.green
+              : (isCurrent ? Colors.black : Colors.grey[300]),
+          child: isDone
+              ? const Icon(Icons.check, size: 14, color: Colors.white)
+              : Text(
+                  '$step',
+                  style: TextStyle(
+                    color: isCurrent ? Colors.white : Colors.black54,
+                    fontSize: 10,
+                  ),
+                ),
        ),
        const SizedBox(height: 4),
-        Text(label, style: TextStyle(fontSize: 9, color: isCurrent ? Colors.black : Colors.grey, fontWeight: isCurrent ? FontWeight.bold : FontWeight.normal)),
+        Text(
+          label,
+          style: TextStyle(
+            fontSize: 9,
+            color: isCurrent ? Colors.black : Colors.grey,
+            fontWeight: isCurrent ? FontWeight.bold : FontWeight.normal,
+          ),
+        ),
      ],
    );
  }
@@ -420,7 +456,6 @@ class _SignupScreenState extends State<SignupScreen> {
        Text(
          tr(
            'msg.userfront.signup.agreement.title',
-            fallback: '서비스 이용을 위해\n약관에 동의해주세요',
          ),
          style: const TextStyle(
            fontSize: 20,
@@ -438,10 +473,7 @@ class _SignupScreenState extends State<SignupScreen> {
          ),
          child: CheckboxListTile(
            title: Text(
-              tr(
-                'ui.userfront.signup.agreement.all',
-                fallback: '모두 동의합니다',
-              ),
+              tr('ui.userfront.signup.agreement.all'),
              style: const TextStyle(fontSize: 15, fontWeight: FontWeight.bold),
            ),
            value: _termsAccepted && _privacyAccepted,
@@ -459,7 +491,6 @@ class _SignupScreenState extends State<SignupScreen> {
        _agreementSection(
          title: tr(
            'ui.userfront.signup.agreement.tos_title',
-            fallback: '바론 소프트웨어 이용약관 (필수)',
          ),
          content: _tosText,
          value: _termsAccepted,
@@ -469,7 +500,6 @@ class _SignupScreenState extends State<SignupScreen> {
        _agreementSection(
          title: tr(
            'ui.userfront.signup.agreement.privacy_title',
-            fallback: '개인정보 수집 및 이용 동의 (필수)',
          ),
          content: _privacyText,
          value: _privacyAccepted,
@@ -488,8 +518,10 @@ class _SignupScreenState extends State<SignupScreen> {
    return Column(
      children: [
        CheckboxListTile(
-          title: Text(title,
-              style: const TextStyle(fontSize: 14, fontWeight: FontWeight.w600)),
+          title: Text(
+            title,
+            style: const TextStyle(fontSize: 14, fontWeight: FontWeight.w600),
+          ),
          value: value,
          onChanged: onChanged,
          controlAffinity: ListTileControlAffinity.leading,
@@ -508,7 +540,11 @@ class _SignupScreenState extends State<SignupScreen> {
          child: SingleChildScrollView(
            child: Text(
              content,
-              style: const TextStyle(fontSize: 12, color: Colors.grey, height: 1.5),
+              style: const TextStyle(
+                fontSize: 12,
+                color: Colors.grey,
+                height: 1.5,
+              ),
            ),
          ),
        ),
@@ -517,8 +553,8 @@ class _SignupScreenState extends State<SignupScreen> {
  }

  static String get _tosText => tr(
-        'msg.userfront.signup.tos_full',
-        fallback: """
+    'msg.userfront.signup.tos_full',
+    fallback: """
 바론 소프트웨어 이용약관

 제1장 총칙
@@ -589,11 +625,11 @@ class _SignupScreenState extends State<SignupScreen> {
 부칙
 본 약관은 2024년 10월 1일부터 시행됩니다.
 """,
-      );
+  );

  static String get _privacyText => tr(
-        'msg.userfront.signup.privacy_full',
-        fallback: """
+    'msg.userfront.signup.privacy_full',
+    fallback: """
 개인정보 수집 및 이용 동의

 바론서비스 개인정보처리방침
@@ -702,7 +738,7 @@ class _SignupScreenState extends State<SignupScreen> {
 제8조 (기타)
 본 방침에 명시되지 않은 사항은 회사의 내부 방침과 관련 법령에 따릅니다.
 """,
-      );
+  );

  Widget _buildStepAuth() {
    return Column(
@@ -711,7 +747,6 @@ class _SignupScreenState extends State<SignupScreen> {
        Text(
          tr(
            'msg.userfront.signup.auth.title',
-            fallback: '본인 확인을 위해\n인증을 진행해주세요',
          ),
          style: const TextStyle(fontSize: 20, fontWeight: FontWeight.bold),
        ),
@@ -719,7 +754,10 @@ class _SignupScreenState extends State<SignupScreen> {
        // 가족사 이메일 안내 문구
        Container(
          padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 8),
-          decoration: BoxDecoration(color: Colors.blue[50], borderRadius: BorderRadius.circular(6)),
+          decoration: BoxDecoration(
+            color: Colors.blue[50],
+            borderRadius: BorderRadius.circular(6),
+          ),
          child: Row(
            children: [
              const Icon(Icons.info_outline, size: 16, color: Colors.blue),
@@ -728,9 +766,12 @@ class _SignupScreenState extends State<SignupScreen> {
                child: Text(
                  tr(
                    'msg.userfront.signup.auth.affiliate_notice',
-                    fallback: '가족사 회원의 경우 반드시 회사 공식 이메일을 입력해주세요.',
                  ),
-                  style: const TextStyle(fontSize: 12, color: Colors.blue, fontWeight: FontWeight.w500),
+                  style: const TextStyle(
+                    fontSize: 12,
+                    color: Colors.blue,
+                    fontWeight: FontWeight.w500,
+                  ),
                ),
              ),
            ],
@@ -738,7 +779,7 @@ class _SignupScreenState extends State<SignupScreen> {
        ),
        const SizedBox(height: 24),
        Text(
-          tr('ui.userfront.signup.auth.email.title', fallback: '이메일 인증'),
+          tr('ui.userfront.signup.auth.email.title'),
          style: const TextStyle(fontWeight: FontWeight.bold),
        ),
        const SizedBox(height: 8),
@@ -751,9 +792,8 @@ class _SignupScreenState extends State<SignupScreen> {
                decoration: InputDecoration(
                  labelText: tr(
                    'ui.userfront.signup.auth.email.label',
-                    fallback: '이메일 주소',
                  ),
-                  border: const OutlineInputBorder(), 
+                  border: const OutlineInputBorder(),
                  errorText: _emailError,
                  hintText: 'example@hanmaceng.co.kr',
                ),
@@ -764,14 +804,19 @@ class _SignupScreenState extends State<SignupScreen> {
            SizedBox(
              height: 55,
              child: ElevatedButton(
-                onPressed: (_isEmailVerified || _isLoading) ? null : _sendEmailCode,
-                style: ElevatedButton.styleFrom(backgroundColor: Colors.grey[100], foregroundColor: Colors.black, elevation: 0),
+                onPressed: (_isEmailVerified || _isLoading)
+                    ? null
+                    : _sendEmailCode,
+                style: ElevatedButton.styleFrom(
+                  backgroundColor: Colors.grey[100],
+                  foregroundColor: Colors.black,
+                  elevation: 0,
+                ),
                child: Text(
                  _emailSeconds > 0
-                      ? tr('ui.common.resend', fallback: '재발송')
+                      ? tr('ui.common.resend')
                      : tr(
                          'ui.userfront.signup.auth.request_code',
-                          fallback: '인증요청',
                        ),
                ),
              ),
@@ -785,14 +830,18 @@ class _SignupScreenState extends State<SignupScreen> {
            decoration: InputDecoration(
              labelText: tr(
                'ui.userfront.signup.auth.code_label',
-                fallback: '인증코드 6자리',
              ),
              suffixText: _formatTime(_emailSeconds),
              border: const OutlineInputBorder(),
            ),
            keyboardType: TextInputType.number,
-            inputFormatters: [FilteringTextInputFormatter.digitsOnly, LengthLimitingTextInputFormatter(6)],
-            onChanged: (val) { if(val.length == 6) _verifyEmailCode(); },
+            inputFormatters: [
+              FilteringTextInputFormatter.digitsOnly,
+              LengthLimitingTextInputFormatter(6),
+            ],
+            onChanged: (val) {
+              if (val.length == 6) _verifyEmailCode();
+            },
          ),
        ],
        if (_isEmailVerified)
@@ -801,7 +850,6 @@ class _SignupScreenState extends State<SignupScreen> {
            child: Text(
              tr(
                'msg.userfront.signup.email.verified',
-                fallback: '✅ 이메일 인증 완료',
              ),
              style: const TextStyle(
                color: Colors.green,
@@ -812,7 +860,7 @@ class _SignupScreenState extends State<SignupScreen> {
          ),
        const SizedBox(height: 24),
        Text(
-          tr('ui.userfront.signup.phone.title', fallback: '휴대폰 인증'),
+          tr('ui.userfront.signup.phone.title'),
          style: const TextStyle(fontWeight: FontWeight.bold),
        ),
        const SizedBox(height: 8),
@@ -824,7 +872,6 @@ class _SignupScreenState extends State<SignupScreen> {
                decoration: InputDecoration(
                  labelText: tr(
                    'ui.userfront.signup.phone.label',
-                    fallback: '휴대폰 번호 (-없이)',
                  ),
                  border: const OutlineInputBorder(),
                  errorText: _phoneError,
@@ -837,14 +884,19 @@ class _SignupScreenState extends State<SignupScreen> {
            SizedBox(
              height: 55,
              child: ElevatedButton(
-                onPressed: (_isPhoneVerified || _isLoading) ? null : _sendPhoneCode,
-                style: ElevatedButton.styleFrom(backgroundColor: Colors.grey[100], foregroundColor: Colors.black, elevation: 0),
+                onPressed: (_isPhoneVerified || _isLoading)
+                    ? null
+                    : _sendPhoneCode,
+                style: ElevatedButton.styleFrom(
+                  backgroundColor: Colors.grey[100],
+                  foregroundColor: Colors.black,
+                  elevation: 0,
+                ),
                child: Text(
                  _phoneSeconds > 0
-                      ? tr('ui.common.resend', fallback: '재발송')
+                      ? tr('ui.common.resend')
                      : tr(
                          'ui.userfront.signup.auth.request_code',
-                          fallback: '인증요청',
                        ),
                ),
              ),
@@ -858,14 +910,18 @@ class _SignupScreenState extends State<SignupScreen> {
            decoration: InputDecoration(
              labelText: tr(
                'ui.userfront.signup.auth.code_label',
-                fallback: '인증코드 6자리',
              ),
              suffixText: _formatTime(_phoneSeconds),
              border: const OutlineInputBorder(),
            ),
            keyboardType: TextInputType.number,
-            inputFormatters: [FilteringTextInputFormatter.digitsOnly, LengthLimitingTextInputFormatter(6)],
-            onChanged: (val) { if(val.length == 6) _verifyPhoneCode(); },
+            inputFormatters: [
+              FilteringTextInputFormatter.digitsOnly,
+              LengthLimitingTextInputFormatter(6),
+            ],
+            onChanged: (val) {
+              if (val.length == 6) _verifyPhoneCode();
+            },
          ),
        ],
        if (_isPhoneVerified)
@@ -874,7 +930,6 @@ class _SignupScreenState extends State<SignupScreen> {
            child: Text(
              tr(
                'msg.userfront.signup.phone.verified',
-                fallback: '✅ 휴대폰 인증 완료',
              ),
              style: const TextStyle(
                color: Colors.green,
@@ -894,7 +949,6 @@ class _SignupScreenState extends State<SignupScreen> {
        Text(
          tr(
            'msg.userfront.signup.profile.title',
-            fallback: '회원님의\n소속 정보를 알려주세요',
          ),
          style: const TextStyle(fontSize: 20, fontWeight: FontWeight.bold),
        ),
@@ -903,10 +957,7 @@ class _SignupScreenState extends State<SignupScreen> {
          controller: _nameController,
          onChanged: (_) => setState(() {}),
          decoration: InputDecoration(
-            labelText: tr(
-              'ui.userfront.signup.profile.name',
-              fallback: '이름',
-            ),
+            labelText: tr('ui.userfront.signup.profile.name'),
            border: const OutlineInputBorder(),
          ),
        ),
@@ -922,13 +973,11 @@ class _SignupScreenState extends State<SignupScreen> {
              decoration: InputDecoration(
                labelText: tr(
                  'ui.userfront.signup.profile.affiliation_type',
-                  fallback: '소속 유형',
                ),
                border: const OutlineInputBorder(),
                helperText: _isAffiliateEmail
                    ? tr(
                        'msg.userfront.signup.profile.affiliate_hint',
-                        fallback: '가족사 이메일 사용 시 자동으로 선택됩니다.',
                      )
                    : null,
              ),
@@ -936,19 +985,13 @@ class _SignupScreenState extends State<SignupScreen> {
                DropdownMenuItem(
                  value: 'GENERAL',
                  child: Text(
-                    tr(
-                      'domain.affiliation.general',
-                      fallback: '일반 사용자',
-                    ),
+                    tr('domain.affiliation.general'),
                  ),
                ),
                DropdownMenuItem(
                  value: 'AFFILIATE',
                  child: Text(
-                    tr(
-                      'domain.affiliation.affiliate',
-                      fallback: '가족사 임직원',
-                    ),
+                    tr('domain.affiliation.affiliate'),
                  ),
                ),
              ],
@@ -978,46 +1021,33 @@ class _SignupScreenState extends State<SignupScreen> {
                decoration: InputDecoration(
                  labelText: tr(
                    'ui.userfront.signup.profile.company',
-                    fallback: '가족사 선택',
                  ),
                  border: const OutlineInputBorder(),
                ),
                items: [
                  DropdownMenuItem(
                    value: 'HANMAC',
-                    child: Text(
-                      tr('domain.company.hanmac', fallback: '한맥'),
-                    ),
+                    child: Text(tr('domain.company.hanmac')),
                  ),
                  DropdownMenuItem(
                    value: 'SAMAN',
-                    child: Text(
-                      tr('domain.company.saman', fallback: '삼안'),
-                    ),
+                    child: Text(tr('domain.company.saman')),
                  ),
                  DropdownMenuItem(
                    value: 'PTC',
-                    child: Text(
-                      tr('domain.company.ptc', fallback: 'PTC'),
-                    ),
+                    child: Text(tr('domain.company.ptc', fallback: 'PTC')),
                  ),
                  DropdownMenuItem(
                    value: 'JANGHEON',
-                    child: Text(
-                      tr('domain.company.jangheon', fallback: '장헌'),
-                    ),
+                    child: Text(tr('domain.company.jangheon')),
                  ),
                  DropdownMenuItem(
                    value: 'BARON',
-                    child: Text(
-                      tr('domain.company.baron', fallback: '바론'),
-                    ),
+                    child: Text(tr('domain.company.baron')),
                  ),
                  DropdownMenuItem(
                    value: 'HALLA',
-                    child: Text(
-                      tr('domain.company.halla', fallback: '한라'),
-                    ),
+                    child: Text(tr('domain.company.halla')),
                  ),
                ],
                onChanged: _isAffiliateEmail
@@ -1033,12 +1063,11 @@ class _SignupScreenState extends State<SignupScreen> {
          onChanged: (_) => setState(() {}),
          decoration: InputDecoration(
            labelText: _affiliationType == 'AFFILIATE'
-                ? tr('ui.userfront.signup.profile.department', fallback: '부서명')
+                ? tr('ui.userfront.signup.profile.department')
                : tr(
                    'ui.userfront.signup.profile.department_optional',
-                    fallback: '소속 정보 (선택)',
                  ),
-            border: const OutlineInputBorder()
+            border: const OutlineInputBorder(),
          ),
        ),
      ],
@@ -1049,7 +1078,6 @@ class _SignupScreenState extends State<SignupScreen> {
    if (_isPolicyLoading) {
      return tr(
        'msg.userfront.signup.policy.loading',
-        fallback: '비밀번호 정책을 불러오는 중입니다...',
      );
    }
    final minLength = (_policy?['minLength'] as int?) ?? 12;
@@ -1062,7 +1090,6 @@ class _SignupScreenState extends State<SignupScreen> {
    final parts = <String>[
      tr(
        'msg.userfront.signup.policy.min_length',
-        fallback: '최소 {{count}}자 이상',
        params: {'count': minLength.toString()},
      ),
    ];
@@ -1070,54 +1097,32 @@ class _SignupScreenState extends State<SignupScreen> {
      parts.add(
        tr(
          'msg.userfront.signup.policy.min_types',
-          fallback: '영문 대/소문자/숫자/특수문자 중 {{count}}가지 이상',
          params: {'count': minTypes.toString()},
        ),
      );
    }
    if (requiresUpper) {
-      parts.add(
-        tr(
-          'msg.userfront.signup.policy.uppercase',
-          fallback: '대문자',
-        ),
-      );
+      parts.add(tr('msg.userfront.signup.policy.uppercase'));
    }
    if (requiresLower) {
-      parts.add(
-        tr(
-          'msg.userfront.signup.policy.lowercase',
-          fallback: '소문자',
-        ),
-      );
+      parts.add(tr('msg.userfront.signup.policy.lowercase'));
    }
    if (requiresNumber) {
-      parts.add(
-        tr(
-          'msg.userfront.signup.policy.number',
-          fallback: '숫자',
-        ),
-      );
+      parts.add(tr('msg.userfront.signup.policy.number'));
    }
    if (requiresSymbol) {
-      parts.add(
-        tr(
-          'msg.userfront.signup.policy.symbol',
-          fallback: '특수문자',
-        ),
-      );
+      parts.add(tr('msg.userfront.signup.policy.symbol'));
    }

    return tr(
      'msg.userfront.signup.policy.summary',
-      fallback: '보안 정책: {{rules}}',
      params: {'rules': parts.join(', ')},
    );
  }

  Widget _buildStepPassword() {
    String p = _passwordController.text;
-    
+
    // Default Policy Fallback
    final minLength = (_policy?['minLength'] as int?) ?? 12;
    final minTypes = (_policy?['minCharacterTypes'] as int?) ?? 0;
@@ -1144,7 +1149,6 @@ class _SignupScreenState extends State<SignupScreen> {
        Text(
          tr(
            'msg.userfront.signup.password.title',
-            fallback: '마지막으로\n비밀번호를 설정해주세요',
          ),
          style: const TextStyle(fontSize: 20, fontWeight: FontWeight.bold),
        ),
@@ -1152,7 +1156,10 @@ class _SignupScreenState extends State<SignupScreen> {
        // 비밀번호 정책 안내 박스
        Container(
          padding: const EdgeInsets.all(12),
-          decoration: BoxDecoration(color: Colors.blue[50], borderRadius: BorderRadius.circular(8)),
+          decoration: BoxDecoration(
+            color: Colors.blue[50],
+            borderRadius: BorderRadius.circular(8),
+          ),
          child: Row(
            children: [
              const Icon(Icons.security, size: 18, color: Colors.blue),
@@ -1160,7 +1167,11 @@ class _SignupScreenState extends State<SignupScreen> {
              Expanded(
                child: Text(
                  _buildPolicyDescription(),
-                  style: TextStyle(fontSize: 12, color: Colors.blue[800], fontWeight: FontWeight.w500),
+                  style: TextStyle(
+                    fontSize: 12,
+                    color: Colors.blue[800],
+                    fontWeight: FontWeight.w500,
+                  ),
                ),
              ),
            ],
@@ -1174,7 +1185,6 @@ class _SignupScreenState extends State<SignupScreen> {
          decoration: InputDecoration(
            labelText: tr(
              'ui.userfront.signup.password.label',
-              fallback: '비밀번호',
            ),
            border: const OutlineInputBorder(),
            errorText: _passwordError,
@@ -1187,7 +1197,6 @@ class _SignupScreenState extends State<SignupScreen> {
            _cryptoCheck(
              tr(
                'msg.userfront.signup.password.rule.min_length',
-                fallback: '{{count}}자 이상',
                params: {'count': minLength.toString()},
              ),
              hasLength,
@@ -1196,7 +1205,6 @@ class _SignupScreenState extends State<SignupScreen> {
              _cryptoCheck(
                tr(
                  'msg.userfront.signup.password.rule.min_types',
-                  fallback: '문자 유형 {{count}}가지 이상',
                  params: {'count': minTypes.toString()},
                ),
                hasTypeCount,
@@ -1205,7 +1213,6 @@ class _SignupScreenState extends State<SignupScreen> {
              _cryptoCheck(
                tr(
                  'msg.userfront.signup.password.rule.uppercase',
-                  fallback: '대문자',
                ),
                hasUpper,
              ),
@@ -1213,23 +1220,18 @@ class _SignupScreenState extends State<SignupScreen> {
              _cryptoCheck(
                tr(
                  'msg.userfront.signup.password.rule.lowercase',
-                  fallback: '소문자',
                ),
                hasLower,
              ),
            if (requiresNumber)
              _cryptoCheck(
-                tr(
-                  'msg.userfront.signup.password.rule.number',
-                  fallback: '숫자',
-                ),
+                tr('msg.userfront.signup.password.rule.number'),
                hasDigit,
              ),
            if (requiresSymbol)
              _cryptoCheck(
                tr(
                  'msg.userfront.signup.password.rule.symbol',
-                  fallback: '특수문자',
                ),
                hasSpecial,
              ),
@@ -1244,7 +1246,6 @@ class _SignupScreenState extends State<SignupScreen> {
              _confirmPasswordError = (val != _passwordController.text)
                  ? tr(
                      'msg.userfront.signup.password.mismatch',
-                      fallback: '비밀번호가 일치하지 않습니다.',
                    )
                  : null;
            });
@@ -1252,8 +1253,7 @@ class _SignupScreenState extends State<SignupScreen> {
          decoration: InputDecoration(
            labelText: tr(
              'ui.userfront.signup.password.confirm_label',
-              fallback: '비밀번호 확인',
-            ), 
+            ),
            border: const OutlineInputBorder(),
            errorText: _confirmPasswordError,
          ),
@@ -1266,9 +1266,19 @@ class _SignupScreenState extends State<SignupScreen> {
    return Row(
      mainAxisSize: MainAxisSize.min,
      children: [
-        Icon(isValid ? Icons.check_circle : Icons.circle_outlined, size: 14, color: isValid ? Colors.green : Colors.grey),
+        Icon(
+          isValid ? Icons.check_circle : Icons.circle_outlined,
+          size: 14,
+          color: isValid ? Colors.green : Colors.grey,
+        ),
        const SizedBox(width: 4),
-        Text(label, style: TextStyle(fontSize: 11, color: isValid ? Colors.green : Colors.grey)),
+        Text(
+          label,
+          style: TextStyle(
+            fontSize: 11,
+            color: isValid ? Colors.green : Colors.grey,
+          ),
+        ),
      ],
    );
  }
@@ -1276,8 +1286,10 @@ class _SignupScreenState extends State<SignupScreen> {
  @override
  Widget build(BuildContext context) {
    bool canGoNext = false;
-    if (_currentStep == 1 && _termsAccepted && _privacyAccepted) canGoNext = true;
-    if (_currentStep == 2 && _isEmailVerified && _isPhoneVerified) canGoNext = true;
+    if (_currentStep == 1 && _termsAccepted && _privacyAccepted)
+      canGoNext = true;
+    if (_currentStep == 2 && _isEmailVerified && _isPhoneVerified)
+      canGoNext = true;
    if (_currentStep == 3) {
      final nameOk = _nameController.text.trim().isNotEmpty;
      if (_affiliationType == 'GENERAL') {
@@ -1294,7 +1306,7 @@ class _SignupScreenState extends State<SignupScreen> {
      backgroundColor: Colors.white,
      appBar: AppBar(
        title: Text(
-          tr('ui.userfront.signup.title', fallback: '회원가입'),
+          tr('ui.userfront.signup.title'),
          style: const TextStyle(fontWeight: FontWeight.bold),
        ),
        elevation: 0,
@@ -1313,11 +1325,13 @@ class _SignupScreenState extends State<SignupScreen> {
                padding: const EdgeInsets.all(24),
                child: Form(
                  key: _formKey,
-                  child: _currentStep == 1 
-                    ? _buildStepAgreement() 
-                    : (_currentStep == 2 
-                        ? _buildStepAuth() 
-                        : (_currentStep == 3 ? _buildStepInfo() : _buildStepPassword())),
+                  child: _currentStep == 1
+                      ? _buildStepAgreement()
+                      : (_currentStep == 2
+                            ? _buildStepAuth()
+                            : (_currentStep == 3
+                                  ? _buildStepInfo()
+                                  : _buildStepPassword())),
                ),
              ),
            ),
@@ -1329,9 +1343,12 @@ class _SignupScreenState extends State<SignupScreen> {
                    Expanded(
                      child: OutlinedButton(
                        onPressed: () => setState(() => _currentStep--),
-                        style: OutlinedButton.styleFrom(minimumSize: const Size.fromHeight(55), side: const BorderSide(color: Colors.black)),
+                        style: OutlinedButton.styleFrom(
+                          minimumSize: const Size.fromHeight(55),
+                          side: const BorderSide(color: Colors.black),
+                        ),
                        child: Text(
-                          tr('ui.common.prev', fallback: '이전'),
+                          tr('ui.common.prev'),
                          style: const TextStyle(color: Colors.black),
                        ),
                      ),
@@ -1340,20 +1357,33 @@ class _SignupScreenState extends State<SignupScreen> {
                  ],
                  Expanded(
                    child: FilledButton(
-                      onPressed: _currentStep < 4 
-                        ? (canGoNext ? () => setState(() => _currentStep++) : null)
-                        : (_isLoading ? null : _handleSignup),
+                      onPressed: _currentStep < 4
+                          ? (canGoNext
+                                ? () => setState(() => _currentStep++)
+                                : null)
+                          : (_isLoading ? null : _handleSignup),
                      style: FilledButton.styleFrom(
                        minimumSize: const Size.fromHeight(55),
                        backgroundColor: Colors.black,
                      ),
-                      child: _isLoading 
-                        ? const SizedBox(height: 20, width: 20, child: CircularProgressIndicator(color: Colors.white, strokeWidth: 2))
-                        : Text(
-                            _currentStep < 4
-                                ? tr('ui.userfront.signup.next_step', fallback: '다음 단계')
-                                : tr('ui.userfront.signup.complete', fallback: '가입 완료'),
-                          ),
+                      child: _isLoading
+                          ? const SizedBox(
+                              height: 20,
+                              width: 20,
+                              child: CircularProgressIndicator(
+                                color: Colors.white,
+                                strokeWidth: 2,
+                              ),
+                            )
+                          : Text(
+                              _currentStep < 4
+                                  ? tr(
+                                      'ui.userfront.signup.next_step',
+                                    )
+                                  : tr(
+                                      'ui.userfront.signup.complete',
+                                    ),
+                            ),
                    ),
                  ),
                ],
--- a/userfront/lib/features/dashboard/domain/dashboard_providers.dart
+++ b/userfront/lib/features/dashboard/domain/dashboard_providers.dart
@@ -181,7 +181,6 @@ class AuthTimelineNotifier extends Notifier<AuthTimelineState> {
        isLoadingMore: false,
        error: tr(
          'msg.userfront.dashboard.timeline.load_error',
-          fallback: '접속이력을 불러오지 못했습니다.',
        ),
      );
    }
--- a/userfront/lib/features/dashboard/presentation/dashboard_screen.dart
+++ b/userfront/lib/features/dashboard/presentation/dashboard_screen.dart
--- a/userfront/lib/features/profile/data/repositories/profile_repository.dart
+++ b/userfront/lib/features/profile/data/repositories/profile_repository.dart
@@ -25,7 +25,7 @@ class ProfileRepository {
    final useCookie = AuthTokenStore.usesCookie();
    if (token == null && !useCookie) {
      throw Exception(
-        tr('err.userfront.session.missing', fallback: '활성 세션이 없습니다.'),
+        tr('err.userfront.session.missing'),
      );
    }

@@ -46,7 +46,6 @@ class ProfileRepository {
      throw Exception(
        tr(
          'err.userfront.profile.load_failed',
-          fallback: '프로필을 불러오지 못했습니다: {{error}}',
          params: {'error': response.body},
        ),
      );
@@ -62,7 +61,7 @@ class ProfileRepository {
    final useCookie = AuthTokenStore.usesCookie();
    if (token == null && !useCookie) {
      throw Exception(
-        tr('err.userfront.session.missing', fallback: '활성 세션이 없습니다.'),
+        tr('err.userfront.session.missing'),
      );
    }

@@ -89,7 +88,6 @@ class ProfileRepository {
      throw Exception(
        tr(
          'err.userfront.profile.update_failed',
-          fallback: '프로필 업데이트에 실패했습니다: {{error}}',
          params: {'error': response.body},
        ),
      );
@@ -101,7 +99,7 @@ class ProfileRepository {
    final useCookie = AuthTokenStore.usesCookie();
    if (token == null && !useCookie) {
      throw Exception(
-        tr('err.userfront.session.missing', fallback: '활성 세션이 없습니다.'),
+        tr('err.userfront.session.missing'),
      );
    }

@@ -124,7 +122,6 @@ class ProfileRepository {
      throw Exception(
        tr(
          'err.userfront.profile.send_code_failed',
-          fallback: '인증번호 전송 실패: {{error}}',
          params: {'error': response.body},
        ),
      );
@@ -139,7 +136,7 @@ class ProfileRepository {
    final useCookie = AuthTokenStore.usesCookie();
    if (token == null && !useCookie) {
      throw Exception(
-        tr('err.userfront.session.missing', fallback: '활성 세션이 없습니다.'),
+        tr('err.userfront.session.missing'),
      );
    }

@@ -165,7 +162,6 @@ class ProfileRepository {
      throw Exception(
        tr(
          'err.userfront.profile.password_change_failed',
-          fallback: '비밀번호 변경에 실패했습니다: {{error}}',
          params: {'error': response.body},
        ),
      );
@@ -177,7 +173,7 @@ class ProfileRepository {
    final useCookie = AuthTokenStore.usesCookie();
    if (token == null && !useCookie) {
      throw Exception(
-        tr('err.userfront.session.missing', fallback: '활성 세션이 없습니다.'),
+        tr('err.userfront.session.missing'),
      );
    }

@@ -200,7 +196,6 @@ class ProfileRepository {
      throw Exception(
        tr(
          'err.userfront.profile.verify_code_failed',
-          fallback: '인증 실패: {{error}}',
          params: {'error': response.body},
        ),
      );
--- a/userfront/lib/features/profile/presentation/pages/profile_page.dart
+++ b/userfront/lib/features/profile/presentation/pages/profile_page.dart
@@ -5,6 +5,7 @@ import 'package:userfront/i18n.dart';
 import '../../../../core/notifiers/auth_notifier.dart';
 import '../../../../core/services/auth_token_store.dart';
 import '../../../../core/ui/layout_breakpoints.dart';
+import '../../../../core/widgets/language_selector.dart';
 import '../../data/models/user_profile_model.dart';
 import '../../domain/notifiers/profile_notifier.dart';

@@ -140,7 +141,8 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
    if (_editingField != 'name' && _nameController!.text != profile.name) {
      _nameController!.text = profile.name;
    }
-    if (_editingField != 'department' && _departmentController!.text != profile.department) {
+    if (_editingField != 'department' &&
+        _departmentController!.text != profile.department) {
      _departmentController!.text = profile.department;
    }
    if (_editingField != 'phone' && _phoneController!.text != profile.phone) {
@@ -234,7 +236,6 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
            content: Text(
              tr(
                'msg.userfront.profile.phone.code_sent',
-                fallback: '인증번호가 전송되었습니다.',
              ),
            ),
          ),
@@ -248,7 +249,6 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
            content: Text(
              tr(
                'msg.userfront.profile.phone.send_failed',
-                fallback: '전송 실패: {{error}}',
                params: {'error': e.toString()},
              ),
            ),
@@ -274,10 +274,7 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(
            content: Text(
-              tr(
-                'msg.userfront.profile.phone.verified',
-                fallback: '인증되었습니다.',
-              ),
+              tr('msg.userfront.profile.phone.verified'),
            ),
          ),
        );
@@ -293,7 +290,6 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
            content: Text(
              tr(
                'msg.userfront.profile.phone.verify_failed',
-                fallback: '인증 실패: {{error}}',
                params: {'error': e.toString()},
              ),
            ),
@@ -310,24 +306,27 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
    final confirmPassword = _confirmPasswordController?.text.trim() ?? '';

    if (currentPassword.isEmpty) {
-      setState(() => _passwordError = tr(
-            'msg.userfront.profile.password.current_required',
-            fallback: '현재 비밀번호를 입력해 주세요.',
-          ));
+      setState(
+        () => _passwordError = tr(
+          'msg.userfront.profile.password.current_required',
+        ),
+      );
      return;
    }
    if (newPassword.isEmpty) {
-      setState(() => _passwordError = tr(
-            'msg.userfront.profile.password.new_required',
-            fallback: '새 비밀번호를 입력해 주세요.',
-          ));
+      setState(
+        () => _passwordError = tr(
+          'msg.userfront.profile.password.new_required',
+        ),
+      );
      return;
    }
    if (newPassword != confirmPassword) {
-      setState(() => _passwordError = tr(
-            'msg.userfront.profile.password.mismatch',
-            fallback: '새 비밀번호가 일치하지 않습니다.',
-          ));
+      setState(
+        () => _passwordError = tr(
+          'msg.userfront.profile.password.mismatch',
+        ),
+      );
      return;
    }

@@ -338,7 +337,9 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
    });

    try {
-      await ref.read(profileRepositoryProvider).changePassword(
+      await ref
+          .read(profileRepositoryProvider)
+          .changePassword(
            currentPassword: currentPassword,
            newPassword: newPassword,
          );
@@ -348,7 +349,6 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
      setState(() {
        _passwordSuccess = tr(
          'msg.userfront.profile.password.changed',
-          fallback: '비밀번호가 변경되었습니다.',
        );
      });
    } catch (e) {
@@ -356,7 +356,6 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
      setState(() {
        _passwordError = tr(
          'msg.userfront.profile.password.change_failed',
-          fallback: '비밀번호 변경 실패: {{error}}',
          params: {'error': message},
        );
      });
@@ -434,10 +433,7 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
      ScaffoldMessenger.of(context).showSnackBar(
        SnackBar(
          content: Text(
-            tr(
-              'msg.userfront.profile.name_required',
-              fallback: '이름을 입력해주세요.',
-            ),
+            tr('msg.userfront.profile.name_required'),
          ),
        ),
      );
@@ -449,7 +445,6 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
          content: Text(
            tr(
              'msg.userfront.profile.department_required',
-              fallback: '소속을 입력해주세요.',
            ),
          ),
        ),
@@ -463,7 +458,6 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
            content: Text(
              tr(
                'msg.userfront.profile.phone_required',
-                fallback: '휴대폰 번호를 입력해주세요.',
              ),
            ),
          ),
@@ -476,7 +470,6 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
            content: Text(
              tr(
                'msg.userfront.profile.phone_verify_required',
-                fallback: '휴대폰 번호 인증이 필요합니다.',
              ),
            ),
          ),
@@ -500,7 +493,9 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
    _isSavingField = true;

    try {
-      await ref.read(profileProvider.notifier).updateProfile(
+      await ref
+          .read(profileProvider.notifier)
+          .updateProfile(
            name: nextName,
            phone: nextPhone,
            department: nextDepartment,
@@ -520,7 +515,6 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
            content: Text(
              tr(
                'msg.userfront.profile.update_success',
-                fallback: '정보가 수정되었습니다.',
              ),
            ),
          ),
@@ -533,7 +527,6 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
            content: Text(
              tr(
                'msg.userfront.profile.update_failed',
-                fallback: '수정 실패: {{error}}',
                params: {'error': e.toString()},
              ),
            ),
@@ -546,38 +539,40 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
  }

  Widget _buildSideMenu(BuildContext context) {
-    return ListView(
-      padding: const EdgeInsets.symmetric(vertical: 12),
+    return Column(
      children: [
-        ListTile(
-          leading: const Icon(Icons.home_outlined),
-          title: Text(
-            tr('ui.userfront.nav.dashboard', fallback: '대시보드'),
+        Expanded(
+          child: ListView(
+            padding: const EdgeInsets.symmetric(vertical: 12),
+            children: [
+              ListTile(
+                leading: const Icon(Icons.home_outlined),
+                title: Text(tr('ui.userfront.nav.dashboard')),
+                onTap: () => context.go('/'),
+              ),
+              ListTile(
+                leading: const Icon(Icons.person_outline),
+                title: Text(tr('ui.userfront.nav.profile')),
+                selected: true,
+                onTap: () => context.go('/profile'),
+              ),
+              ListTile(
+                leading: const Icon(Icons.qr_code_scanner),
+                title: Text(tr('ui.userfront.nav.qr_scan')),
+                onTap: () => context.go('/scan'),
+              ),
+              const Divider(),
+              ListTile(
+                leading: const Icon(Icons.logout),
+                title: Text(tr('ui.userfront.nav.logout')),
+                onTap: _logout,
+              ),
+            ],
          ),
-          onTap: () => context.go('/'),
        ),
-        ListTile(
-          leading: const Icon(Icons.person_outline),
-          title: Text(
-            tr('ui.userfront.nav.profile', fallback: '내 정보'),
-          ),
-          selected: true,
-          onTap: () => context.go('/profile'),
-        ),
-        ListTile(
-          leading: const Icon(Icons.qr_code_scanner),
-          title: Text(
-            tr('ui.userfront.nav.qr_scan', fallback: 'QR 스캔'),
-          ),
-          onTap: () => context.go('/scan'),
-        ),
-        const Divider(),
-        ListTile(
-          leading: const Icon(Icons.logout),
-          title: Text(
-            tr('ui.userfront.nav.logout', fallback: '로그아웃'),
-          ),
-          onTap: _logout,
+        const Padding(
+          padding: EdgeInsets.only(bottom: 16),
+          child: LanguageSelector(compact: true),
        ),
      ],
    );
@@ -589,13 +584,14 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
      children: [
        Text(
          title,
-          style: const TextStyle(fontSize: 18, fontWeight: FontWeight.w700, color: _ink),
+          style: const TextStyle(
+            fontSize: 18,
+            fontWeight: FontWeight.w700,
+            color: _ink,
+          ),
        ),
        const SizedBox(width: 12),
-        Text(
-          subtitle,
-          style: TextStyle(fontSize: 13, color: Colors.grey[600]),
-        ),
+        Text(subtitle, style: TextStyle(fontSize: 13, color: Colors.grey[600])),
      ],
    );
  }
@@ -615,7 +611,11 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
          const SizedBox(width: 6),
          Text(
            label,
-            style: const TextStyle(fontSize: 12, color: _ink, fontWeight: FontWeight.w600),
+            style: const TextStyle(
+              fontSize: 12,
+              color: _ink,
+              fontWeight: FontWeight.w600,
+            ),
          ),
        ],
      ),
@@ -624,13 +624,13 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {

  Widget _buildHeaderCard(UserProfile profile) {
    final name = profile.name.isEmpty
-        ? tr('msg.userfront.profile.name_missing', fallback: '이름 없음')
+        ? tr('msg.userfront.profile.name_missing')
        : profile.name;
    final email = profile.email.isEmpty
-        ? tr('msg.userfront.profile.email_missing', fallback: '이메일 없음')
+        ? tr('msg.userfront.profile.email_missing')
        : profile.email;
    final department = profile.department.isEmpty
-        ? tr('msg.userfront.profile.department_missing', fallback: '소속 정보 없음')
+        ? tr('msg.userfront.profile.department_missing')
        : profile.department;

    return Container(
@@ -650,10 +650,7 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
      ),
      child: Row(
        children: [
-          const CircleAvatar(
-            radius: 32,
-            child: Icon(Icons.person, size: 32),
-          ),
+          const CircleAvatar(radius: 32, child: Icon(Icons.person, size: 32)),
          const SizedBox(width: 16),
          Expanded(
            child: Column(
@@ -662,7 +659,6 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
                Text(
                  tr(
                    'msg.userfront.profile.greeting',
-                    fallback: '안녕하세요, {{name}}님',
                    params: {'name': name},
                  ),
                  style: const TextStyle(
@@ -672,7 +668,10 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
                  ),
                ),
                const SizedBox(height: 6),
-                Text(email, style: TextStyle(color: Colors.grey[600], fontSize: 14)),
+                Text(
+                  email,
+                  style: TextStyle(color: Colors.grey[600], fontSize: 14),
+                ),
                const SizedBox(height: 12),
                Wrap(
                  spacing: 8,
@@ -680,9 +679,12 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
                  children: [
                    _buildInfoChip(
                      Icons.badge_outlined,
-                      tr('ui.userfront.profile.manage', fallback: '프로필 관리'),
+                      tr('ui.userfront.profile.manage'),
+                    ),
+                    _buildInfoChip(
+                      Icons.apartment,
+                      profile.tenant?.name ?? department,
                    ),
-                    _buildInfoChip(Icons.apartment, profile.tenant?.name ?? department),
                  ],
                ),
              ],
@@ -720,7 +722,7 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
      title: Text(label),
      subtitle: Text(displayValue),
      trailing: Text(
-        tr('ui.common.read_only', fallback: '읽기 전용'),
+        tr('ui.common.read_only'),
        style: TextStyle(color: Colors.grey[500], fontSize: 12),
      ),
    );
@@ -744,7 +746,7 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
        subtitle: Text(displayValue),
        trailing: TextButton(
          onPressed: isUpdating ? null : () => _startEditing(field, profile),
-          child: Text(tr('ui.common.edit', fallback: '수정')),
+          child: Text(tr('ui.common.edit')),
        ),
      );
    }
@@ -772,7 +774,7 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
            const SizedBox(width: 12),
            OutlinedButton(
              onPressed: isUpdating ? null : () => _cancelEditing(profile),
-              child: Text(tr('ui.common.cancel', fallback: '취소')),
+              child: Text(tr('ui.common.cancel')),
            ),
          ],
        ),
@@ -787,13 +789,11 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
    if (!isEditing) {
      return ListTile(
        contentPadding: EdgeInsets.zero,
-        title: Text(
-          tr('ui.userfront.profile.phone.title', fallback: '전화번호'),
-        ),
+        title: Text(tr('ui.userfront.profile.phone.title')),
        subtitle: Text(displayValue),
        trailing: TextButton(
          onPressed: isUpdating ? null : () => _startEditing('phone', profile),
-          child: Text(tr('ui.common.edit', fallback: '수정')),
+          child: Text(tr('ui.common.edit')),
        ),
      );
    }
@@ -802,7 +802,7 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
      crossAxisAlignment: CrossAxisAlignment.start,
      children: [
        Text(
-          tr('ui.userfront.profile.phone.title', fallback: '전화번호'),
+          tr('ui.userfront.profile.phone.title'),
          style: const TextStyle(fontWeight: FontWeight.w600),
        ),
        const SizedBox(height: 8),
@@ -832,17 +832,16 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
                onPressed: _isVerifying ? null : _sendCode,
                child: Text(
                  _isCodeSent
-                      ? tr('ui.common.resend', fallback: '재전송')
+                      ? tr('ui.common.resend')
                      : tr(
                          'ui.userfront.profile.phone.request_code',
-                          fallback: '인증요청',
                        ),
                ),
              ),
            const SizedBox(width: 8),
            OutlinedButton(
              onPressed: isUpdating ? null : () => _cancelEditing(profile),
-              child: Text(tr('ui.common.cancel', fallback: '취소')),
+              child: Text(tr('ui.common.cancel')),
            ),
          ],
        ),
@@ -862,7 +861,6 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
                    border: const OutlineInputBorder(),
                    hintText: tr(
                      'ui.userfront.profile.phone.code_hint',
-                      fallback: '인증번호 6자리',
                    ),
                  ),
                ),
@@ -870,7 +868,7 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
              const SizedBox(width: 8),
              ElevatedButton(
                onPressed: _isVerifying ? null : () => _verifyCode(profile),
-                child: Text(tr('ui.common.confirm', fallback: '확인')),
+                child: Text(tr('ui.common.confirm')),
              ),
            ],
          ),
@@ -881,7 +879,6 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
            child: Text(
              tr(
                'msg.userfront.profile.phone.verify_notice',
-                fallback: '휴대폰 번호를 변경하려면 SMS 인증이 필요합니다.',
              ),
              style: const TextStyle(color: Colors.orange, fontSize: 12),
            ),
@@ -896,14 +893,13 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Text(
-            tr('ui.userfront.profile.password.title', fallback: '비밀번호 변경'),
+            tr('ui.userfront.profile.password.title'),
            style: const TextStyle(fontSize: 16, fontWeight: FontWeight.w700),
          ),
          const SizedBox(height: 8),
          Text(
            tr(
              'msg.userfront.profile.password.subtitle',
-              fallback: '현재 비밀번호 확인 후 새 비밀번호로 변경합니다.',
            ),
            style: const TextStyle(color: Color(0xFF6B7280)),
          ),
@@ -914,11 +910,14 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
            decoration: InputDecoration(
              labelText: tr(
                'ui.userfront.profile.password.current',
-                fallback: '현재 비밀번호',
              ),
              border: const OutlineInputBorder(),
              suffixIcon: IconButton(
-                icon: Icon(_showCurrentPassword ? Icons.visibility_off : Icons.visibility),
+                icon: Icon(
+                  _showCurrentPassword
+                      ? Icons.visibility_off
+                      : Icons.visibility,
+                ),
                onPressed: () => setState(() {
                  _showCurrentPassword = !_showCurrentPassword;
                }),
@@ -932,11 +931,12 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
            decoration: InputDecoration(
              labelText: tr(
                'ui.userfront.profile.password.new',
-                fallback: '새 비밀번호',
              ),
              border: const OutlineInputBorder(),
              suffixIcon: IconButton(
-                icon: Icon(_showNewPassword ? Icons.visibility_off : Icons.visibility),
+                icon: Icon(
+                  _showNewPassword ? Icons.visibility_off : Icons.visibility,
+                ),
                onPressed: () => setState(() {
                  _showNewPassword = !_showNewPassword;
                }),
@@ -950,11 +950,14 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
            decoration: InputDecoration(
              labelText: tr(
                'ui.userfront.profile.password.confirm',
-                fallback: '새 비밀번호 확인',
              ),
              border: const OutlineInputBorder(),
              suffixIcon: IconButton(
-                icon: Icon(_showConfirmPassword ? Icons.visibility_off : Icons.visibility),
+                icon: Icon(
+                  _showConfirmPassword
+                      ? Icons.visibility_off
+                      : Icons.visibility,
+                ),
                onPressed: () => setState(() {
                  _showConfirmPassword = !_showConfirmPassword;
                }),
@@ -963,10 +966,7 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
          ),
          if (_passwordError != null) ...[
            const SizedBox(height: 12),
-            Text(
-              _passwordError!,
-              style: const TextStyle(color: Colors.red),
-            ),
+            Text(_passwordError!, style: const TextStyle(color: Colors.red)),
          ],
          if (_passwordSuccess != null) ...[
            const SizedBox(height: 12),
@@ -989,7 +989,6 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
                    : Text(
                        tr(
                          'ui.userfront.profile.password.change',
-                          fallback: '비밀번호 변경',
                        ),
                      ),
              ),
@@ -999,7 +998,6 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
                child: Text(
                  tr(
                    'ui.userfront.profile.password.forgot',
-                    fallback: '비밀번호를 잊으셨나요?',
                  ),
                ),
              ),
@@ -1025,10 +1023,9 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
                  _buildHeaderCard(profile),
                  const SizedBox(height: 28),
                  _buildSectionTitle(
-                    tr('ui.userfront.profile.section.basic', fallback: '기본 정보'),
+                    tr('ui.userfront.profile.section.basic'),
                    tr(
                      'msg.userfront.profile.section.basic',
-                      fallback: '계정 기본 정보를 관리합니다.',
                    ),
                  ),
                  const SizedBox(height: 12),
@@ -1037,7 +1034,9 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
                      children: [
                        _buildEditableTile(
                          field: 'name',
-                          label: tr('ui.userfront.profile.field.name', fallback: '이름'),
+                          label: tr(
+                            'ui.userfront.profile.field.name',
+                          ),
                          value: profile.name,
                          profile: profile,
                          isUpdating: isUpdating,
@@ -1045,7 +1044,9 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
                        ),
                        const Divider(height: 24),
                        _buildReadOnlyTile(
-                          tr('ui.userfront.profile.field.email', fallback: '이메일'),
+                          tr(
+                            'ui.userfront.profile.field.email',
+                          ),
                          profile.email,
                        ),
                        const Divider(height: 24),
@@ -1055,10 +1056,11 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
                  ),
                  const SizedBox(height: 28),
                  _buildSectionTitle(
-                    tr('ui.userfront.profile.section.organization', fallback: '조직 정보'),
+                    tr(
+                      'ui.userfront.profile.section.organization',
+                    ),
                    tr(
                      'msg.userfront.profile.section.organization',
-                      fallback: '소속 및 구분 정보입니다.',
                    ),
                  ),
                  const SizedBox(height: 12),
@@ -1067,7 +1069,9 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
                      children: [
                        _buildEditableTile(
                          field: 'department',
-                          label: tr('ui.userfront.profile.field.department', fallback: '소속'),
+                          label: tr(
+                            'ui.userfront.profile.field.department',
+                          ),
                          value: profile.department,
                          profile: profile,
                          isUpdating: isUpdating,
@@ -1075,7 +1079,9 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
                        ),
                        const Divider(height: 24),
                        _buildReadOnlyTile(
-                          tr('ui.userfront.profile.field.affiliation', fallback: '구분'),
+                          tr(
+                            'ui.userfront.profile.field.affiliation',
+                          ),
                          profile.affiliationType,
                        ),
                        if (profile.tenant != null) ...[
@@ -1083,7 +1089,6 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
                          _buildReadOnlyTile(
                            tr(
                              'ui.userfront.profile.field.tenant',
-                              fallback: '소속 테넌트',
                            ),
                            profile.tenant!.name,
                          ),
@@ -1091,7 +1096,9 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
                        if (profile.companyCode.isNotEmpty) ...[
                          const Divider(height: 24),
                          _buildReadOnlyTile(
-                            tr('ui.userfront.profile.field.company_code', fallback: '회사코드'),
+                            tr(
+                              'ui.userfront.profile.field.company_code',
+                            ),
                            profile.companyCode,
                          ),
                        ],
@@ -1100,10 +1107,9 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
                  ),
                  const SizedBox(height: 28),
                  _buildSectionTitle(
-                    tr('ui.userfront.profile.section.security', fallback: '보안'),
+                    tr('ui.userfront.profile.section.security'),
                    tr(
                      'msg.userfront.profile.section.security',
-                      fallback: '비밀번호를 안전하게 관리합니다.',
                    ),
                  ),
                  const SizedBox(height: 12),
@@ -1132,7 +1138,7 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
    if (profile == null) {
      return Scaffold(
        appBar: AppBar(
-          title: Text(tr('ui.userfront.nav.profile', fallback: '내 정보')),
+          title: Text(tr('ui.userfront.nav.profile')),
        ),
        body: profileState.isLoading
            ? const Center(child: CircularProgressIndicator())
@@ -1143,13 +1149,13 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
                    Text(
                      tr(
                        'msg.userfront.profile.load_failed',
-                        fallback: '정보를 불러올 수 없습니다.',
                      ),
                    ),
                    const SizedBox(height: 16),
                    ElevatedButton(
-                      onPressed: () => ref.read(profileProvider.notifier).loadProfile(),
-                      child: Text(tr('ui.common.retry', fallback: '재시도')),
+                      onPressed: () =>
+                          ref.read(profileProvider.notifier).loadProfile(),
+                      child: Text(tr('ui.common.retry')),
                    ),
                  ],
                ),
@@ -1166,7 +1172,7 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
      backgroundColor: _subtle,
      appBar: AppBar(
        title: Text(
-          tr('ui.userfront.app_title', fallback: 'Baron 로그인'),
+          tr('ui.userfront.app_title'),
          style: const TextStyle(fontWeight: FontWeight.bold),
        ),
        elevation: 0,
@@ -1175,17 +1181,17 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
        actions: [
          IconButton(
            icon: const Icon(Icons.home_outlined),
-            tooltip: tr('ui.userfront.nav.dashboard', fallback: '대시보드'),
+            tooltip: tr('ui.userfront.nav.dashboard'),
            onPressed: () => context.go('/'),
          ),
          IconButton(
            icon: const Icon(Icons.qr_code_scanner),
-            tooltip: tr('ui.userfront.nav.qr_scan', fallback: 'QR 스캔'),
+            tooltip: tr('ui.userfront.nav.qr_scan'),
            onPressed: () => context.push('/scan'),
          ),
          IconButton(
            icon: const Icon(Icons.logout),
-            tooltip: tr('ui.userfront.nav.logout', fallback: '로그아웃'),
+            tooltip: tr('ui.userfront.nav.logout'),
            onPressed: _logout,
          ),
        ],
@@ -1193,11 +1199,7 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
      drawer: isWide ? null : Drawer(child: _buildSideMenu(context)),
      body: Row(
        children: [
-          if (isWide)
-            SizedBox(
-              width: 240,
-              child: _buildSideMenu(context),
-            ),
+          if (isWide) SizedBox(width: 240, child: _buildSideMenu(context)),
          Expanded(child: _buildContent(profile, isUpdating)),
        ],
      ),
--- a/userfront/lib/i18n.dart
+++ b/userfront/lib/i18n.dart
@@ -1,40 +1,18 @@
-import 'dart:ui';
+import 'package:easy_localization/easy_localization.dart';

-import 'i18n_data.dart';
+final _koreanPattern = RegExp(r'[가-힣]');

-const _defaultLocale = 'ko';
-const _supportedLocales = ['ko', 'en'];
-
-String _resolveLocale() {
-  final locale = PlatformDispatcher.instance.locale;
-  final code = locale.languageCode.toLowerCase();
-  if (_supportedLocales.contains(code)) {
-    return code;
+String tr(String key, {String? fallback, Map<String, String>? params}) {
+  try {
+    if (fallback != null && _koreanPattern.hasMatch(fallback)) {
+      fallback = null;
+    }
+    final translated = key.tr(namedArgs: params);
+    if (translated == key && fallback != null && fallback.isNotEmpty) {
+      return fallback;
+    }
+    return translated;
+  } catch (_) {
+    return fallback ?? key;
  }
-  return _defaultLocale;
-}
-
-String _formatTemplate(String template, Map<String, String>? params) {
-  if (params == null || params.isEmpty) {
-    return template;
-  }
-  var result = template;
-  params.forEach((key, value) {
-    result = result.replaceAll('{{$key}}', value);
-  });
-  return result;
-}
-
-String tr(
-  String key, {
-  String? fallback,
-  Map<String, String>? params,
-}) {
-  final locale = _resolveLocale();
-  final map = locale == 'en' ? enStrings : koStrings;
-  final value = map[key];
-  final template = (value != null && value.isNotEmpty)
-      ? value
-      : (fallback ?? key);
-  return _formatTemplate(template, params);
 }
--- a/userfront/lib/main.dart
+++ b/userfront/lib/main.dart
@@ -2,6 +2,7 @@ import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:flutter_dotenv/flutter_dotenv.dart';
+import 'package:easy_localization/easy_localization.dart' hide tr;
 import 'package:go_router/go_router.dart';
 import 'package:flutter/services.dart';
 import 'package:flutter_web_plugins/url_strategy.dart';
@@ -19,6 +20,9 @@ import 'core/services/auth_proxy_service.dart';
 import 'core/services/auth_token_store.dart';
 import 'core/services/logger_service.dart';
 import 'core/notifiers/auth_notifier.dart';
+import 'core/i18n/locale_gate.dart';
+import 'core/i18n/locale_utils.dart';
+import 'core/i18n/toml_asset_loader.dart';
 import 'package:logging/logging.dart';
 import 'features/auth/presentation/consent_screen.dart';
 import 'i18n.dart';
@@ -40,13 +44,16 @@ Future<void> _loadBundledFonts() async {
 void main() async {
  WidgetsFlutterBinding.ensureInitialized();
  usePathUrlStrategy();
+  await EasyLocalization.ensureInitialized();

  // 1. Global Error Handling
  FlutterError.onError = (details) {
    FlutterError.presentError(details);
    _log.severe("FLUTTER_ERROR", details.exception, details.stack);
    // Also send to backend if needed
-    AuthProxyService.logError("FLUTTER_ERROR: ${details.exception}\n${details.stack}");
+    AuthProxyService.logError(
+      "FLUTTER_ERROR: ${details.exception}\n${details.stack}",
+    );
  };

  PlatformDispatcher.instance.onError = (error, stack) {
@@ -68,7 +75,22 @@ void main() async {
  // 폰트를 먼저 로딩해서 렌더링 깨짐(FOIT/FOUT) 최소화
  await _loadBundledFonts();

-  runApp(const ProviderScope(child: BaronSSOApp()));
+  runApp(
+    // URL(/en, /ko)이 있으면 우선 적용해서 첫 렌더부터 올바른 언어로 시작합니다.
+    () {
+      final initialLocaleCode =
+          extractLocaleFromPath(Uri.base) ?? resolvePreferredLocaleCode();
+      return EasyLocalization(
+        supportedLocales: const [Locale('en'), Locale('ko')],
+        fallbackLocale: const Locale('en'),
+        startLocale: Locale(initialLocaleCode),
+        saveLocale: false,
+        path: 'assets/translations',
+        assetLoader: const TomlAssetLoader(),
+        child: const ProviderScope(child: BaronSSOApp()),
+      );
+    }(),
+  );
 }

 // Router Configuration
@@ -79,190 +101,227 @@ final _router = GoRouter(
  debugLogDiagnostics: !kReleaseMode,
  refreshListenable: AuthNotifier.instance,
  routes: [
-    GoRoute(
-      path: '/',
-      builder: (context, state) {
-        _routerLogger.info("Navigating to root (DashboardScreen)");
-        return const DashboardScreen();
-      },
-    ),
-    GoRoute(
-      path: '/profile',
-      builder: (context, state) => const ProfilePage(),
-    ),
-    GoRoute(
-      path: '/signin',
-      builder: (context, state) {
-        final loginChallenge = state.uri.queryParameters['login_challenge'];
-        _routerLogger.info("Navigating to /signin with login_challenge: $loginChallenge");
-        return LoginScreen(key: state.pageKey, loginChallenge: loginChallenge);
-      },
-    ),
-    GoRoute(
-      path: '/login',
-      builder: (context, state) {
-        _routerLogger.info("Navigating to /login");
-        return LoginScreen(key: state.pageKey);
-      },
-    ),
-    GoRoute(
-      path: '/consent',
-      builder: (BuildContext context, GoRouterState state) {
-        final consentChallenge = state.uri.queryParameters['consent_challenge'];
-        if (consentChallenge == null) {
-          _routerLogger.warning("Consent screen loaded without a challenge.");
-          return const Scaffold(body: Center(child: Text('Error: Consent challenge is missing.')));
-        }
-        _routerLogger.info("Navigating to /consent with challenge.");
-        return ConsentScreen(consentChallenge: consentChallenge);
-      },
-    ),
-    GoRoute(
-      path: '/signup',
-      builder: (context, state) {
-        _routerLogger.info("Navigating to /signup");
-        return const SignupScreen();
-      },
-    ),
-    GoRoute(
-      path: '/registration',
-      builder: (context, state) {
-        _routerLogger.info("Navigating to /registration");
-        return const SignupScreen();
-      },
-    ),
-    GoRoute(
-      path: '/verify',
-      builder: (context, state) {
-        _routerLogger.info("Navigating to /verify (query)");
-        return LoginScreen(key: state.pageKey);
-      },
-    ),
-    GoRoute(
-      path: '/verify/:token',
-      builder: (context, state) {
-        final token = state.pathParameters['token'];
-        _routerLogger.info("Navigating to /verify with token: $token");
-        return LoginScreen(key: state.pageKey, verificationToken: token);
-      },
-    ),
-    GoRoute(
-      path: '/verification',
-      builder: (context, state) {
-        _routerLogger.info("Navigating to /verification");
-        return LoginScreen(key: state.pageKey);
-      },
-    ),
-    GoRoute(
-      path: '/l/:shortCode',
-      builder: (context, state) {
-        final shortCode = state.pathParameters['shortCode'];
-        _routerLogger.info("Navigating to /l with code: $shortCode");
-        return LoginScreen(key: state.pageKey);
-      },
-    ),
-    GoRoute(
-      path: '/forgot-password',
-      builder: (context, state) {
-        _routerLogger.info("Navigating to /forgot-password");
-        return const ForgotPasswordScreen();
-      },
-    ),
-    GoRoute(
-      path: '/recovery',
-      builder: (context, state) {
-        _routerLogger.info("Navigating to /recovery");
-        return const ForgotPasswordScreen();
-      },
-    ),
-    GoRoute(
-      // Supports both /reset-password and /reset-password?token=...
-      path: '/reset-password',
-      builder: (context, state) {
-        // For deep linking, you might pass the token in the path, e.g., /reset-password/:token
-        // final token = state.pathParameters['token'];
-        _routerLogger.info("Navigating to /reset-password");
-        return const ResetPasswordScreen();
-      },
-    ),
-    GoRoute(
-      path: '/error',
-      builder: (context, state) {
-        _routerLogger.info("Navigating to /error");
-        final params = state.uri.queryParameters;
-        return ErrorScreen(
-          errorId: params['id'],
-          errorCode: params['error'],
-          description: params['error_description'] ?? params['message'],
-        );
-      },
-    ),
-    GoRoute(
-      path: '/settings',
-      builder: (context, state) {
-        _routerLogger.info("Navigating to /settings (disabled)");
-        return ErrorScreen(
-          errorCode: 'settings_disabled',
-          description: tr(
-            'msg.userfront.settings.disabled',
-            fallback: '현재 계정 설정 화면은 준비 중입니다.',
-          ),
-        );
-      },
-    ),
-    GoRoute(
-      path: '/approve',
-      builder: (context, state) {
-        final ref = state.uri.queryParameters['ref'];
-        _routerLogger.info("Navigating to /approve with ref: $ref");
-        return ApproveQrScreen(pendingRef: ref);
-      },
-    ),
-    GoRoute(
-      path: '/ql/:ref',
-      builder: (context, state) {
-        final ref = state.pathParameters['ref'];
-        _routerLogger.info("Navigating to /ql with ref: $ref");
-        return ApproveQrScreen(pendingRef: ref);
-      },
-    ),
-    GoRoute(
-      path: '/scan',
-      builder: (context, state) {
-        _routerLogger.info("Navigating to /scan");
-        return const QRScanScreen();
-      },
-    ),
-    GoRoute(
-      path: '/admin/users',
-      builder: (context, state) {
-        _routerLogger.info("Navigating to /admin/users");
-        return const UserManagementScreen();
+    ShellRoute(
+      builder: (context, state, child) {
+        final localeCode =
+            extractLocaleFromPath(state.uri) ?? resolvePreferredLocaleCode();
+        return LocaleGate(localeCode: localeCode, child: child);
      },
+      routes: [
+        GoRoute(
+          path: '/:locale',
+          builder: (context, state) {
+            _routerLogger.info("Navigating to root (DashboardScreen)");
+            return const DashboardScreen();
+          },
+          routes: [
+            GoRoute(
+              path: 'profile',
+              builder: (context, state) => const ProfilePage(),
+            ),
+            GoRoute(
+              path: 'signin',
+              builder: (context, state) {
+                final loginChallenge =
+                    state.uri.queryParameters['login_challenge'];
+                final redirectUrl =
+                    state.uri.queryParameters['redirect_uri'] ??
+                    state.uri.queryParameters['redirect_url'];
+                _routerLogger.info(
+                  "Navigating to /signin with login_challenge: $loginChallenge, redirect: $redirectUrl",
+                );
+                return LoginScreen(
+                  key: state.pageKey,
+                  loginChallenge: loginChallenge,
+                  redirectUrl: redirectUrl,
+                );
+              },
+            ),
+            GoRoute(
+              path: 'login',
+              builder: (context, state) {
+                final redirectUrl =
+                    state.uri.queryParameters['redirect_uri'] ??
+                    state.uri.queryParameters['redirect_url'];
+                _routerLogger.info("Navigating to /login, redirect: $redirectUrl");
+                return LoginScreen(key: state.pageKey, redirectUrl: redirectUrl);
+              },
+            ),
+            GoRoute(
+              path: 'consent',
+              builder: (BuildContext context, GoRouterState state) {
+                final consentChallenge =
+                    state.uri.queryParameters['consent_challenge'];
+                if (consentChallenge == null) {
+                  _routerLogger.warning("Consent screen loaded without a challenge.");
+                  return const Scaffold(
+                    body: Center(
+                      child: Text('Error: Consent challenge is missing.'),
+                    ),
+                  );
+                }
+                _routerLogger.info("Navigating to /consent with challenge.");
+                return ConsentScreen(consentChallenge: consentChallenge);
+              },
+            ),
+            GoRoute(
+              path: 'signup',
+              builder: (context, state) {
+                _routerLogger.info("Navigating to /signup");
+                return const SignupScreen();
+              },
+            ),
+            GoRoute(
+              path: 'registration',
+              builder: (context, state) {
+                _routerLogger.info("Navigating to /registration");
+                return const SignupScreen();
+              },
+            ),
+            GoRoute(
+              path: 'verify',
+              builder: (context, state) {
+                _routerLogger.info("Navigating to /verify (query)");
+                return LoginScreen(key: state.pageKey);
+              },
+            ),
+            GoRoute(
+              path: 'verify/:token',
+              builder: (context, state) {
+                final token = state.pathParameters['token'];
+                _routerLogger.info("Navigating to /verify with token: $token");
+                return LoginScreen(
+                  key: state.pageKey,
+                  verificationToken: token,
+                );
+              },
+            ),
+            GoRoute(
+              path: 'verification',
+              builder: (context, state) {
+                _routerLogger.info("Navigating to /verification");
+                return LoginScreen(key: state.pageKey);
+              },
+            ),
+            GoRoute(
+              path: 'l/:shortCode',
+              builder: (context, state) {
+                final shortCode = state.pathParameters['shortCode'];
+                _routerLogger.info("Navigating to /l with code: $shortCode");
+                return LoginScreen(key: state.pageKey);
+              },
+            ),
+            GoRoute(
+              path: 'forgot-password',
+              builder: (context, state) {
+                _routerLogger.info("Navigating to /forgot-password");
+                return const ForgotPasswordScreen();
+              },
+            ),
+            GoRoute(
+              path: 'recovery',
+              builder: (context, state) {
+                _routerLogger.info("Navigating to /recovery");
+                return const ForgotPasswordScreen();
+              },
+            ),
+            GoRoute(
+              // Supports both /reset-password and /reset-password?token=...
+              path: 'reset-password',
+              builder: (context, state) {
+                _routerLogger.info("Navigating to /reset-password");
+                return const ResetPasswordScreen();
+              },
+            ),
+            GoRoute(
+              path: 'error',
+              builder: (context, state) {
+                _routerLogger.info("Navigating to /error");
+                final params = state.uri.queryParameters;
+                return ErrorScreen(
+                  errorId: params['id'],
+                  errorCode: params['error'],
+                  description:
+                      params['error_description'] ?? params['message'],
+                );
+              },
+            ),
+            GoRoute(
+              path: 'settings',
+              builder: (context, state) {
+                _routerLogger.info("Navigating to /settings (disabled)");
+                return ErrorScreen(
+                  errorCode: 'settings_disabled',
+                  description: tr(
+                    'msg.userfront.settings.disabled',
+                  ),
+                );
+              },
+            ),
+            GoRoute(
+              path: 'approve',
+              builder: (context, state) {
+                final ref = state.uri.queryParameters['ref'];
+                _routerLogger.info("Navigating to /approve with ref: $ref");
+                return ApproveQrScreen(pendingRef: ref);
+              },
+            ),
+            GoRoute(
+              path: 'ql/:ref',
+              builder: (context, state) {
+                final ref = state.pathParameters['ref'];
+                _routerLogger.info("Navigating to /ql with ref: $ref");
+                return ApproveQrScreen(pendingRef: ref);
+              },
+            ),
+            GoRoute(
+              path: 'scan',
+              builder: (context, state) {
+                _routerLogger.info("Navigating to /scan");
+                return const QRScanScreen();
+              },
+            ),
+            GoRoute(
+              path: 'admin/users',
+              builder: (context, state) {
+                _routerLogger.info("Navigating to /admin/users");
+                return const UserManagementScreen();
+              },
+            ),
+          ],
+        ),
+      ],
    ),
  ],
  redirect: (context, state) {
+    final requestedLocale = extractLocaleFromPath(state.uri);
+    final preferredLocale = resolvePreferredLocaleCode();
+    if (requestedLocale == null) {
+      return buildLocalizedPath(preferredLocale, state.uri);
+    }
+
    final hasStoredToken = AuthTokenStore.getToken() != null;
    final hasCookieSession = AuthTokenStore.usesCookie();
    final isLoggedIn = hasStoredToken || hasCookieSession;
-    final path = state.uri.path;
+    final path = stripLocalePath(state.uri);

    // Public paths that don't require login
-    final isPublicPath = path == '/signin' ||
-                         path == '/signup' ||
-                         path == '/login' ||
-                         path == '/registration' ||
-                         path == '/verify' ||
-                         path == '/verification' ||
-                         path.startsWith('/verify/') ||
-                         path == '/approve' ||
-                         path.startsWith('/ql/') ||
-                         path == '/forgot-password' ||
-                         path == '/recovery' ||
-                         path == '/reset-password' ||
-                         path == '/error' ||
-                         path == '/settings' ||
-                         path == '/consent'; // Consent page is public
+    final isPublicPath =
+        path == '/signin' ||
+        path == '/signup' ||
+        path == '/login' ||
+        path == '/registration' ||
+        path == '/verify' ||
+        path == '/verification' ||
+        path.startsWith('/verify/') ||
+        path == '/approve' ||
+        path.startsWith('/ql/') ||
+        path == '/forgot-password' ||
+        path == '/recovery' ||
+        path == '/reset-password' ||
+        path == '/error' ||
+        path == '/settings' ||
+        path == '/consent'; // Consent page is public

    _routerLogger.fine("Redirect check - Path: $path, IsLoggedIn: $isLoggedIn");

@@ -273,13 +332,14 @@ final _router = GoRouter(

    // If not logged in and trying to access a protected page, redirect to /signin
    if (!isLoggedIn) {
-       _routerLogger.info("Not logged in, redirecting to /signin");
+      _routerLogger.info("Not logged in, redirecting to /signin");
      // Preserve OIDC challenge if present
      final loginChallenge = state.uri.queryParameters['login_challenge'];
+      final locale = requestedLocale;
      if (loginChallenge != null) {
-        return '/signin?login_challenge=$loginChallenge';
+        return '/$locale/signin?login_challenge=$loginChallenge';
      }
-      return '/signin';
+      return '/$locale/signin';
    }

    // If logged in and trying to access login page, redirect to root (dashboard)
@@ -299,7 +359,10 @@ class BaronSSOApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp.router(
-      title: tr('ui.userfront.app_title', fallback: 'Baron 로그인'),
+      title: tr('ui.userfront.app_title'),
+      localizationsDelegates: context.localizationDelegates,
+      supportedLocales: context.supportedLocales,
+      locale: context.locale,
      theme: ThemeData(
        colorScheme: ColorScheme.fromSeed(
          seedColor: const Color(0xFF1A1F2C), // Dark Navy/Black base
--- a/userfront/pubspec.lock
+++ b/userfront/pubspec.lock
@@ -105,6 +105,22 @@ packages:
      url: "https://pub.dev"
    source: hosted
    version: "1.0.8"
+  easy_localization:
+    dependency: "direct main"
+    description:
+      name: easy_localization
+      sha256: "2ccdf9db8fe4d9c5a75c122e6275674508fd0f0d49c827354967b8afcc56bbed"
+      url: "https://pub.dev"
+    source: hosted
+    version: "3.0.8"
+  easy_logger:
+    dependency: transitive
+    description:
+      name: easy_logger
+      sha256: c764a6e024846f33405a2342caf91c62e357c24b02c04dbc712ef232bf30ffb7
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.0.2"
  fake_async:
    dependency: transitive
    description:
@@ -113,6 +129,14 @@ packages:
      url: "https://pub.dev"
    source: hosted
    version: "1.3.3"
+  ffi:
+    dependency: transitive
+    description:
+      name: ffi
+      sha256: "6d7fd89431262d8f3125e81b50d3847a091d846eafcd4fdb88dd06f36d705a45"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.2.0"
  file:
    dependency: transitive
    description:
@@ -134,6 +158,11 @@ packages:
      url: "https://pub.dev"
    source: hosted
    version: "6.0.0"
+  flutter_driver:
+    dependency: transitive
+    description: flutter
+    source: sdk
+    version: "0.0.0"
  flutter_lints:
    dependency: "direct dev"
    description:
@@ -142,6 +171,11 @@ packages:
      url: "https://pub.dev"
    source: hosted
    version: "6.0.0"
+  flutter_localizations:
+    dependency: transitive
+    description: flutter
+    source: sdk
+    version: "0.0.0"
  flutter_riverpod:
    dependency: "direct main"
    description:
@@ -168,6 +202,11 @@ packages:
      url: "https://pub.dev"
    source: hosted
    version: "4.0.0"
+  fuchsia_remote_debug_protocol:
+    dependency: transitive
+    description: flutter
+    source: sdk
+    version: "0.0.0"
  glob:
    dependency: transitive
    description:
@@ -208,6 +247,19 @@ packages:
      url: "https://pub.dev"
    source: hosted
    version: "4.1.2"
+  integration_test:
+    dependency: "direct dev"
+    description: flutter
+    source: sdk
+    version: "0.0.0"
+  intl:
+    dependency: transitive
+    description:
+      name: intl
+      sha256: "3df61194eb431efc39c4ceba583b95633a403f46c9fd341e550ce0bfa50e9aa5"
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.20.2"
  io:
    dependency: transitive
    description:
@@ -336,6 +388,46 @@ packages:
      url: "https://pub.dev"
    source: hosted
    version: "1.9.1"
+  path_provider_linux:
+    dependency: transitive
+    description:
+      name: path_provider_linux
+      sha256: f7a1fe3a634fe7734c8d3f2766ad746ae2a2884abe22e241a8b301bf5cac3279
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.2.1"
+  path_provider_platform_interface:
+    dependency: transitive
+    description:
+      name: path_provider_platform_interface
+      sha256: "88f5779f72ba699763fa3a3b06aa4bf6de76c8e5de842cf6f29e2e06476c2334"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.1.2"
+  path_provider_windows:
+    dependency: transitive
+    description:
+      name: path_provider_windows
+      sha256: bd6f00dbd873bfb70d0761682da2b3a2c2fccc2b9e84c495821639601d81afe7
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.3.0"
+  petitparser:
+    dependency: transitive
+    description:
+      name: petitparser
+      sha256: "07c8f0b1913bcde1ff0d26e57ace2f3012ccbf2b204e070290dad3bb22797646"
+      url: "https://pub.dev"
+    source: hosted
+    version: "6.1.0"
+  platform:
+    dependency: transitive
+    description:
+      name: platform
+      sha256: "5d6b1b0036a5f331ebc77c850ebc8506cbc1e9416c27e59b439f917a902a4984"
+      url: "https://pub.dev"
+    source: hosted
+    version: "3.1.6"
  plugin_platform_interface:
    dependency: transitive
    description:
@@ -352,6 +444,14 @@ packages:
      url: "https://pub.dev"
    source: hosted
    version: "1.5.2"
+  process:
+    dependency: transitive
+    description:
+      name: process
+      sha256: c6248e4526673988586e8c00bb22a49210c258dc91df5227d5da9748ecf79744
+      url: "https://pub.dev"
+    source: hosted
+    version: "5.0.5"
  pub_semver:
    dependency: transitive
    description:
@@ -384,6 +484,62 @@ packages:
      url: "https://pub.dev"
    source: hosted
    version: "3.2.0"
+  shared_preferences:
+    dependency: transitive
+    description:
+      name: shared_preferences
+      sha256: "2939ae520c9024cb197fc20dee269cd8cdbf564c8b5746374ec6cacdc5169e64"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.5.4"
+  shared_preferences_android:
+    dependency: transitive
+    description:
+      name: shared_preferences_android
+      sha256: cbc40be9be1c5af4dab4d6e0de4d5d3729e6f3d65b89d21e1815d57705644a6f
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.4.20"
+  shared_preferences_foundation:
+    dependency: transitive
+    description:
+      name: shared_preferences_foundation
+      sha256: "4e7eaffc2b17ba398759f1151415869a34771ba11ebbccd1b0145472a619a64f"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.5.6"
+  shared_preferences_linux:
+    dependency: transitive
+    description:
+      name: shared_preferences_linux
+      sha256: "580abfd40f415611503cae30adf626e6656dfb2f0cee8f465ece7b6defb40f2f"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.4.1"
+  shared_preferences_platform_interface:
+    dependency: transitive
+    description:
+      name: shared_preferences_platform_interface
+      sha256: "57cbf196c486bc2cf1f02b85784932c6094376284b3ad5779d1b1c6c6a816b80"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.4.1"
+  shared_preferences_web:
+    dependency: transitive
+    description:
+      name: shared_preferences_web
+      sha256: c49bd060261c9a3f0ff445892695d6212ff603ef3115edbb448509d407600019
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.4.3"
+  shared_preferences_windows:
+    dependency: transitive
+    description:
+      name: shared_preferences_windows
+      sha256: "94ef0f72b2d71bc3e700e025db3710911bd51a71cefb65cc609dd0d9a982e3c1"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.4.1"
  shelf:
    dependency: transitive
    description:
@@ -477,6 +633,14 @@ packages:
      url: "https://pub.dev"
    source: hosted
    version: "1.4.1"
+  sync_http:
+    dependency: transitive
+    description:
+      name: sync_http
+      sha256: "7f0cd72eca000d2e026bcd6f990b81d0ca06022ef4e32fb257b30d3d1014a961"
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.3.1"
  term_glyph:
    dependency: transitive
    description:
@@ -509,6 +673,14 @@ packages:
      url: "https://pub.dev"
    source: hosted
    version: "0.6.12"
+  toml:
+    dependency: "direct main"
+    description:
+      name: toml
+      sha256: "9968de24e45b632bf1a654fe1ac7b6fe5261c349243df83fd262397799c45a2d"
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.15.0"
  typed_data:
    dependency: transitive
    description:
@@ -629,6 +801,14 @@ packages:
      url: "https://pub.dev"
    source: hosted
    version: "3.0.3"
+  webdriver:
+    dependency: transitive
+    description:
+      name: webdriver
+      sha256: "2f3a14ca026957870cfd9c635b83507e0e51d8091568e90129fbf805aba7cade"
+      url: "https://pub.dev"
+    source: hosted
+    version: "3.1.0"
  webkit_inspection_protocol:
    dependency: transitive
    description:
@@ -637,6 +817,14 @@ packages:
      url: "https://pub.dev"
    source: hosted
    version: "1.2.1"
+  xdg_directories:
+    dependency: transitive
+    description:
+      name: xdg_directories
+      sha256: "7a3f37b05d989967cdddcbb571f1ea834867ae2faa29725fd085180e0883aa15"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.1.0"
  yaml:
    dependency: transitive
    description:
@@ -646,5 +834,5 @@ packages:
    source: hosted
    version: "3.1.3"
 sdks:
-  dart: ">=3.10.4 <4.0.0"
+  dart: ">=3.10.0 <4.0.0"
  flutter: ">=3.38.0"
--- a/userfront/pubspec.yaml
+++ b/userfront/pubspec.yaml
@@ -19,7 +19,7 @@ publish_to: "none" # Remove this line if you wish to publish to pub.dev
 version: 1.0.0+1

 environment:
-    sdk: ^3.10.4
+    sdk: ">=3.10.0-0 <4.0.0"

 # Dependencies specify other packages that your package needs in order to work.
 # To automatically upgrade your package dependencies to the latest versions
@@ -45,10 +45,14 @@ dependencies:
    logger: ^2.0.0
    qr_flutter: ^4.1.0
    mobile_scanner: ^7.1.4
+    easy_localization: ^3.0.7
+    toml: ^0.15.0

 dev_dependencies:
    flutter_test:
        sdk: flutter
+    integration_test:
+        sdk: flutter

    # The "flutter_lints" package below contains a set of recommended lints to
    # encourage good coding practices. The lint set provided by the package is
@@ -70,6 +74,8 @@ flutter:
    # To add assets to your application, add an assets section, like this:
    # assets:
    #   - .env
+    assets:
+        - assets/translations/

    # An image asset can refer to one or more resolution-specific "variants", see
    # https://flutter.dev/to/resolution-aware-images
--- a/userfront/test/helpers/web_storage.dart
+++ b/userfront/test/helpers/web_storage.dart
@@ -0,0 +1,5 @@
+import 'web_storage_stub.dart'
+    if (dart.library.html) 'web_storage_web.dart';
+
+export 'web_storage_stub.dart'
+    if (dart.library.html) 'web_storage_web.dart';
--- a/userfront/test/helpers/web_storage_stub.dart
+++ b/userfront/test/helpers/web_storage_stub.dart
@@ -0,0 +1,21 @@
+class WebStorage {
+  bool get isWeb => false;
+
+  String? get(String key) => null;
+
+  void set(String key, String value) {}
+
+  String? getSession(String key) => null;
+
+  void setSession(String key, String value) {}
+
+  void removeSession(String key) {}
+
+  void clearSession() {}
+
+  void remove(String key) {}
+
+  void clear() {}
+}
+
+final webStorage = WebStorage();
--- a/userfront/test/helpers/web_storage_web.dart
+++ b/userfront/test/helpers/web_storage_web.dart
@@ -0,0 +1,37 @@
+// ignore_for_file: avoid_web_libraries_in_flutter
+
+import 'dart:html' as html;
+
+class WebStorage {
+  bool get isWeb => true;
+
+  String? get(String key) => html.window.localStorage[key];
+
+  void set(String key, String value) {
+    html.window.localStorage[key] = value;
+  }
+
+  String? getSession(String key) => html.window.sessionStorage[key];
+
+  void setSession(String key, String value) {
+    html.window.sessionStorage[key] = value;
+  }
+
+  void removeSession(String key) {
+    html.window.sessionStorage.remove(key);
+  }
+
+  void clearSession() {
+    html.window.sessionStorage.clear();
+  }
+
+  void remove(String key) {
+    html.window.localStorage.remove(key);
+  }
+
+  void clear() {
+    html.window.localStorage.clear();
+  }
+}
+
+final webStorage = WebStorage();
--- a/userfront/test/locale_storage_web_test.dart
+++ b/userfront/test/locale_storage_web_test.dart
@@ -0,0 +1,88 @@
+import 'package:flutter_test/flutter_test.dart';
+import 'package:userfront/core/i18n/locale_storage.dart';
+import 'package:userfront/core/i18n/locale_storage_web.dart' as locale_web;
+
+import 'helpers/web_storage.dart';
+
+void main() {
+  setUp(() {
+    locale_web.LocaleStorageImpl.forceMemoryStorageForTests(false);
+    locale_web.LocaleStorageImpl.forceSessionStorageForTests(false);
+    if (webStorage.isWeb) {
+      webStorage.clear();
+      webStorage.clearSession();
+    }
+  });
+
+  tearDown(() {
+    locale_web.LocaleStorageImpl.forceMemoryStorageForTests(false);
+    locale_web.LocaleStorageImpl.forceSessionStorageForTests(false);
+    if (webStorage.isWeb) {
+      webStorage.clear();
+      webStorage.clearSession();
+    }
+  });
+
+  test(
+    'localStorage write/read (웹)',
+    () {
+      if (!webStorage.isWeb) {
+        return;
+      }
+
+      LocaleStorage.write('ko');
+      expect(webStorage.get('locale'), 'ko');
+      expect(LocaleStorage.read(), 'ko');
+    },
+    skip: !webStorage.isWeb,
+  );
+
+  test(
+    'legacy key에서 locale로 마이그레이션 (웹)',
+    () {
+      if (!webStorage.isWeb) {
+        return;
+      }
+
+      webStorage.set('baron_locale', 'en');
+      expect(LocaleStorage.read(), 'en');
+      expect(webStorage.get('locale'), 'en');
+      expect(webStorage.get('baron_locale'), isNull);
+    },
+    skip: !webStorage.isWeb,
+  );
+
+  test(
+    'localStorage 접근이 차단되면 메모리 fallback (웹)',
+    () {
+      if (!webStorage.isWeb) {
+        return;
+      }
+
+      locale_web.LocaleStorageImpl.forceMemoryStorageForTests(true);
+
+      LocaleStorage.write('en');
+      expect(webStorage.get('locale'), isNull);
+      expect(webStorage.getSession('locale'), isNull);
+      expect(LocaleStorage.read(), 'en');
+    },
+    skip: !webStorage.isWeb,
+  );
+
+  test(
+    'localStorage 접근이 차단되면 sessionStorage로 fallback (웹)',
+    () {
+      if (!webStorage.isWeb) {
+        return;
+      }
+
+      locale_web.LocaleStorageImpl.forceSessionStorageForTests(true);
+
+      LocaleStorage.write('ko');
+      expect(webStorage.get('locale'), isNull);
+      expect(webStorage.getSession('locale'), 'ko');
+      expect(LocaleStorage.read(), 'ko');
+    },
+    skip: !webStorage.isWeb,
+  );
+}
--- a/userfront/test/locale_utils_test.dart
+++ b/userfront/test/locale_utils_test.dart
@@ -0,0 +1,66 @@
+import 'package:flutter_test/flutter_test.dart';
+import 'package:userfront/core/i18n/locale_utils.dart';
+
+void main() {
+  group('locale_utils', () {
+    test('normalizeLocaleCode handles supported locales', () {
+      expect(normalizeLocaleCode('ko'), 'ko');
+      expect(normalizeLocaleCode('ko-KR'), 'ko');
+      expect(normalizeLocaleCode('en'), 'en');
+      expect(normalizeLocaleCode('en-US'), 'en');
+    });
+
+    test('normalizeLocaleCode falls back to default', () {
+      expect(normalizeLocaleCode('ja'), defaultLocaleCode);
+      expect(normalizeLocaleCode(null), defaultLocaleCode);
+      expect(normalizeLocaleCode(''), defaultLocaleCode);
+    });
+
+    test('extractLocaleFromPath picks locale when present', () {
+      expect(extractLocaleFromPath(Uri.parse('/ko/signin')), 'ko');
+      expect(extractLocaleFromPath(Uri.parse('/en/profile')), 'en');
+      expect(extractLocaleFromPath(Uri.parse('/ko')), 'ko');
+    });
+
+    test('extractLocaleFromPath returns null when missing', () {
+      expect(extractLocaleFromPath(Uri.parse('/signin')), isNull);
+      expect(extractLocaleFromPath(Uri.parse('/zz/signin')), isNull);
+    });
+
+    test('stripLocalePath removes locale segment', () {
+      expect(stripLocalePath(Uri.parse('/ko/signin')), '/signin');
+      expect(stripLocalePath(Uri.parse('/en/profile')), '/profile');
+      expect(stripLocalePath(Uri.parse('/ko')), '/');
+      expect(stripLocalePath(Uri.parse('/en/')), '/');
+    });
+
+    test('stripLocalePath keeps path without locale', () {
+      expect(stripLocalePath(Uri.parse('/signin')), '/signin');
+      expect(stripLocalePath(Uri.parse('/auth/callback')), '/auth/callback');
+    });
+
+    test('buildLocalizedPath applies locale', () {
+      expect(buildLocalizedPath('ko', Uri.parse('/signin')), '/ko/signin');
+      expect(buildLocalizedPath('en', Uri.parse('/signin')), '/en/signin');
+      expect(buildLocalizedPath('ko', Uri.parse('/')), '/ko');
+      expect(buildLocalizedPath('en', Uri.parse('/')), '/en');
+    });
+
+    test('buildLocalizedPath preserves query parameters', () {
+      final uri = Uri.parse('/signin?redirect_uri=https://example.com');
+      expect(
+        buildLocalizedPath('ko', uri),
+        '/ko/signin?redirect_uri=https%3A%2F%2Fexample.com',
+      );
+    });
+
+    test('buildLocalizedPath replaces existing locale', () {
+      expect(buildLocalizedPath('en', Uri.parse('/ko/signin')), '/en/signin');
+      expect(buildLocalizedPath('ko', Uri.parse('/en/profile')), '/ko/profile');
+    });
+
+    test('buildLocalizedPath drops unknown 2-letter prefix', () {
+      expect(buildLocalizedPath('ko', Uri.parse('/zz/signin')), '/ko/signin');
+    });
+  });
+}
--- a/userfront/test/widget_test.dart
+++ b/userfront/test/widget_test.dart
@@ -5,15 +5,36 @@
 // gestures. You can also use WidgetTester to find child widgets in the widget
 // tree, read text, and verify that the values of widget properties are correct.

+import 'dart:ui';
+
+import 'package:easy_localization/easy_localization.dart';
 import 'package:flutter_test/flutter_test.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';

 import 'package:userfront/main.dart' show BaronSSOApp;

+class _TestAssetLoader extends AssetLoader {
+  const _TestAssetLoader();
+
+  @override
+  Future<Map<String, dynamic>> load(String path, Locale locale) async {
+    return {};
+  }
+}
+
 void main() {
  testWidgets('BaronSSOApp builds', (WidgetTester tester) async {
    // runApp에서 ProviderScope로 감싸서 쓰고 있으니 테스트도 동일하게 감쌈
-    await tester.pumpWidget(const ProviderScope(child: BaronSSOApp()));
+    await tester.pumpWidget(
+      EasyLocalization(
+        supportedLocales: const [Locale('en'), Locale('ko')],
+        fallbackLocale: const Locale('en'),
+        startLocale: const Locale('en'),
+        path: 'assets/translations',
+        assetLoader: const _TestAssetLoader(),
+        child: const ProviderScope(child: BaronSSOApp()),
+      ),
+    );
    await tester.pump(); // 한 프레임 더
  });
 }