fix: kefu permissions use legacy permission table instead of gvsdsdk

Co-authored-by: Cursor <cursoragent@cursor.com>

users/views.py

@@ -6926,13 +6926,14 @@ class KefuStatsView(APIView):
             logger.warning(f"统计接口 phone 不匹配: 请求phone={phone}, 用户phone={current_user.Phone}")
             return Response({'detail': '认证失败'}, status=status.HTTP_401_UNAUTHORIZED)
 
-        # 4. 验证用户类型是否为客服
-        if current_user.UserType not in ('kefu', 'admin'):
+        # 4. 验证是否为后台客服账号
+        from jituan.services.admin_context import is_kefu_backend_account, is_system_super_admin
+        if not is_kefu_backend_account(current_user):
             logger.warning(f"统计接口用户类型非客服: {current_user.UserUID}")
             return Response({'detail': '认证失败'}, status=status.HTTP_401_UNAUTHORIZED)
 
         # 5. 尝试获取客服扩展表数据（管理员跳过）
-        is_admin = current_user.UserType == 'admin' or current_user.IsSuperuser
+        is_admin = is_system_super_admin(current_user)
         if is_admin:
             return Response({
                 'code': 0,