fix: add folder_id and sort_order to AIChatSession model, fix UUID conversion in routes, add migration 0003

app/plugins/builtins/ai_assistant/services.py

@@ -115,7 +115,8 @@ def session_to_response(session: AIChatSession) -> dict[str, Any]:
         "title": session.title,
         "is_pinned": session.is_pinned,
         "is_sidebar": session.is_sidebar,
-        "folder_id": str(session.folder_id) if hasattr(session, 'folder_id') and session.folder_id else None,
+        "folder_id": str(session.folder_id) if session.folder_id else None,
+        "sort_order": session.sort_order,
         "created_at": session.created_at.isoformat() if session.created_at else None,
         "updated_at": session.updated_at.isoformat() if session.updated_at else None,
     }
@@ -141,6 +142,7 @@ def folder_to_response(folder: AIChatFolder) -> dict[str, Any]:
         "name": folder.name,
         "parent_id": str(folder.parent_id) if folder.parent_id else None,
         "user_id": str(folder.user_id),
+        "sort_order": folder.sort_order,
         "created_at": folder.created_at.isoformat() if folder.created_at else None,
     }