fix: 내 정보(UpdateMe) 수정 시 커스텀 필드 로그인 ID 동기화 및 Metadata 필드 추가 (#440)

backend/internal/domain/auth_models.go

@@ -87,10 +87,11 @@ type UserProfileResponse struct {
 }
 
 type UpdateUserRequest struct {
-	Name             string `json:"name"`
-	Phone            string `json:"phone"`
-	Department       string `json:"department"`
-	VerificationCode string `json:"verificationCode,omitempty"` // For phone change
+	Name             string         `json:"name"`
+	Phone            string         `json:"phone"`
+	Department       string         `json:"department"`
+	VerificationCode string         `json:"verificationCode,omitempty"` // For phone change
+	Metadata         map[string]any `json:"metadata,omitempty"`
 }
 
 // PasswordResetInitiateRequest is the request body for initiating a password reset.