fix(devfront): add explicit button type and improve test stability

devfront/src/features/clients/ClientGeneralPage.tsx

@@ -524,16 +524,17 @@ function ClientGeneralPage() {
       if (result?.client?.id) {
         navigate(`/clients/${result.client.id}/settings`);
       }
-      alert(t("msg.dev.clients.general.saved", "설정이 저장되었습니다."));
+      toast(t("msg.dev.clients.general.saved", "설정이 저장되었습니다."));
     },
     onError: (err) => {
       const axiosError = err as AxiosError<{ error?: string }>;
       if (axiosError.response?.status === 403) {
-        alert(
+        toast(
           t(
             "msg.dev.clients.general.save_forbidden",
             "이 RP 설정을 수정할 권한이 없습니다.\n관리자에게 RP 일반 설정 또는 RP 관리자 관계 부여를 요청해 주세요.",
           ),
+          "error",
         );
         return;
       }
@@ -542,7 +543,7 @@ function ClientGeneralPage() {
         axiosError.response?.data?.error ??
         (err as Error)?.message ??
         t("msg.common.unknown_error", "unknown error");
-      alert(
+      toast(
         t(
           "msg.dev.clients.general.save_error",
           "저장에 실패했습니다: {{error}}",
@@ -550,6 +551,7 @@ function ClientGeneralPage() {
             error: errorMessage,
           },
         ),
+        "error",
       );
     },
   });
@@ -558,17 +560,18 @@ function ClientGeneralPage() {
     mutationFn: (id: string) => deleteClient(id),
     onSuccess: () => {
       queryClient.invalidateQueries({ queryKey: ["clients"] });
-      alert(t("msg.dev.clients.deleted", "앱이 삭제되었습니다."));
+      toast(t("msg.dev.clients.deleted", "앱이 삭제되었습니다."));
       navigate("/clients");
     },
     onError: (err) => {
       const errorMessage =
         (err as AxiosError<{ error?: string }>).response?.data?.error ??
         (err as Error)?.message;
-      alert(
+      toast(
         t("msg.dev.clients.delete_error", "삭제 실패: {{error}}", {
           error: errorMessage,
         }),
+        "error",
       );
     },
   });

devfront/src/features/clients/ClientRelationsPage.tsx

@@ -2,6 +2,7 @@ import { useMutation, useQuery, useQueryClient } from "@tanstack/react-query";
 import type { AxiosError } from "axios";
 import { ArrowLeft, Link2, Plus, Trash2 } from "lucide-react";
 import { useDeferredValue, useMemo, useState } from "react";
+import { useAuth } from "react-oidc-context";
 import { Link, useParams } from "react-router-dom";
 import { Badge } from "../../components/ui/badge";
 import { Button } from "../../components/ui/button";
@@ -33,7 +34,6 @@ import {
 } from "../../lib/devApi";
 import { t } from "../../lib/i18n";
 import { resolveProfileRole } from "../../lib/role";
-import { useAuth } from "react-oidc-context";
 import { ClientDetailTabs } from "./ClientDetailTabs";
 
 const relationOptions = [