refac/enh: db session sharing

backend/open_webui/utils/groups.py

@@ -7,6 +7,7 @@ log = logging.getLogger(__name__)
 def apply_default_group_assignment(
     default_group_id: str,
     user_id: str,
+    db=None,
 ) -> None:
     """
     Apply default group assignment to a user if default_group_id is provided.
@@ -17,7 +18,7 @@ def apply_default_group_assignment(
     """
     if default_group_id:
         try:
-            Groups.add_users_to_group(default_group_id, [user_id])
+            Groups.add_users_to_group(default_group_id, [user_id], db=db)
         except Exception as e:
             log.error(
                 f"Failed to add user {user_id} to default group {default_group_id}: {e}"