Fix LAN API base and development CORS regression

backend/tests/test_upload_request_size_middleware.py

@@ -115,6 +115,7 @@ def _install_main_import_stubs() -> dict[str, ModuleType | None]:
         """Returns minimal settings consumed by app.main during test import."""
 
         return SimpleNamespace(
+            app_env="development",
             cors_origins=["http://localhost:5173"],
             max_upload_request_size_bytes=1024,
         )