fix: Admin UI에서 전송한 커스텀 필드(metadata)가 백엔드 Kratos 트레이츠에 빈 배열로 깨져서 저장되는 문제 해결 (#440)

adminfront/src/features/users/UserDetailPage.tsx

@@ -139,7 +139,9 @@ function TenantMetadataFields({
   );
 }
 
-type UserFormValues = UserUpdateRequest & { metadata: Record<string, any> };
+type UserFormValues = Omit<UserUpdateRequest, "metadata"> & {
+  metadata: Record<string, Record<string, any>>;
+};
 
 function UserDetailPage() {
   const params = useParams<{ id: string }>();
@@ -299,7 +301,20 @@ function UserDetailPage() {
   const onSubmit = (data: UserFormValues) => {
     setError(null);
     setSuccessMsg(null);
-    mutation.mutate(data);
+
+    // Filter out undefined/null/empty strings from metadata
+    const cleanMetadata = Object.fromEntries(
+      Object.entries(data.metadata).map(([tenantId, fields]) => {
+        const cleanFields = Object.fromEntries(
+          Object.entries(fields).filter(
+            ([_, v]) => v !== undefined && v !== null && v !== "",
+          ),
+        );
+        return [tenantId, cleanFields];
+      }),
+    );
+
+    mutation.mutate({ ...data, metadata: cleanMetadata });
   };
 
   const handleDelete = () => {