feat: update datetime handling to use UTC and improve type annotations

app/api/auth/router.py

@@ -1,4 +1,5 @@
-from datetime import datetime, timezone
+from datetime import UTC, datetime
+from typing import Annotated
 
 from core.security import (
     AuthContext,
@@ -32,9 +33,9 @@ async def login_handler(payload: LoginInput):
 
 @router.post("/logout", status_code=status.HTTP_204_NO_CONTENT)
 async def logout_handler(
-    auth_context: AuthContext = Depends(get_auth_context),
+    auth_context: Annotated[AuthContext, Depends(get_auth_context)],
 ) -> Response:
-    expires_at = datetime.fromtimestamp(auth_context.payload.exp, tz=timezone.utc)
-    if expires_at > datetime.now(timezone.utc):
+    expires_at = datetime.fromtimestamp(auth_context.payload.exp, tz=UTC)
+    if expires_at > datetime.now(UTC):
         await revoke_token(jti=auth_context.payload.jti, expires_at=expires_at)
     return Response(status_code=status.HTTP_204_NO_CONTENT)