refactor: split LDAP auth into backend/routers/auth.py

backend/tests/conftest.py

@@ -14,6 +14,7 @@ from backend.models import User
 from backend.config_manager import ConfigManager
 from backend.auth import get_current_admin, TokenData
 import backend.routers.users as users_router
+import backend.routers.auth as auth_router
 import backend.routers.categories as categories_router
 
 
@@ -84,8 +85,8 @@ def test_client(test_db: Session) -> Generator[TestClient, None, None]:
 @pytest.fixture(scope="function")
 def mock_ldap() -> Generator[MagicMock, None, None]:
     """Mock LDAP authentication."""
-    with patch("backend.routers.users.ldap3.Server") as mock_server, \
-         patch("backend.routers.users.ldap3.Connection") as mock_conn_class:
+    with patch("backend.routers.auth.ldap3.Server") as mock_server, \
+         patch("backend.routers.auth.ldap3.Connection") as mock_conn_class:
 
         mock_conn = MagicMock()
         mock_conn.bind.return_value = True