fix(storage): Prevent AttributeError when closing uninitialized Postgres engine

laborious/activities/storage.py

@@ -202,6 +202,7 @@ class Storage(Postgres, MinioManager):
 
     def close(self) -> None:
         """Close Storage resources (MinIO client and Postgres engine)."""
+        if hasattr(self, 'engine'):
             Postgres.close(self)
         MinioManager.close(self)