Rescue Paperjet v1 implementation

backend/app/auth/session.py

@@ -1,11 +1,13 @@
 """Session token generation and validation."""
 
 from typing import Any
+
 from fastapi import Response
-from itsdangerous import URLSafeTimedSerializer, BadSignature, SignatureExpired
+from itsdangerous import BadSignature, SignatureExpired, URLSafeTimedSerializer
 
 from app.config import settings
 
+
 def get_serializer() -> URLSafeTimedSerializer:
     """Return a configured URLSafeTimedSerializer."""
     return URLSafeTimedSerializer(settings.SECRET_KEY)
@@ -14,7 +16,7 @@ def create_session(response: Response, user_id: int = 1) -> None:
     """Create a new session token and set it as an HTTP-only cookie."""
     serializer = get_serializer()
     token = serializer.dumps({"user_id": user_id})
-    
+
     response.set_cookie(
         key=settings.COOKIE_NAME,
         value=token,
@@ -41,7 +43,7 @@ def verify_session(token: str) -> int | None:
     serializer = get_serializer()
     try:
         data: dict[str, Any] = serializer.loads(
-            token, 
+            token,
             max_age=settings.COOKIE_MAX_AGE_SECONDS
         )
         return data.get("user_id")