feat: implement local authentication mode and update related components

backend/tests/conftest.py

@@ -1,9 +1,15 @@
 # ruff: noqa: INP001
 """Pytest configuration shared across backend tests."""
 
+import os
 import sys
 from pathlib import Path
 
 ROOT = Path(__file__).resolve().parents[1]
 if str(ROOT) not in sys.path:
     sys.path.insert(0, str(ROOT))
+
+# Tests should fail fast if auth-mode wiring breaks, but still need deterministic
+# defaults during import-time settings initialization.
+os.environ.setdefault("AUTH_MODE", "local")
+os.environ.setdefault("LOCAL_AUTH_TOKEN", "test-local-token")