perf: P1 性能优化批量修复 + kefu 视图拆分

P1 性能优化（避免循环内 N+1 / N 次 DB 查询）：
- shop_order_views._batch_images: 移除 ThreadPoolExecutor 掩盖的 N 次查询，改单次批量 + Python 侧分组
- product_query.DashouHuiyuanList: 5N 查询 -> 3 次批量预取 + 本地闭包判断
- roles.GetRolePermissionView / 用户列表: 循环内 RolePermission/Permission/UserRole/Role -> 批量 __in 预取
- guanli / zuzhang 杜次分红 4.2/4.3: 循环内 update_or_create + 单条 delete -> bulk_create + bulk_update + 批量 delete
- admin_config QQ 群配置: 循环内 exists/first/save/create -> 批量预取 + bulk_create + bulk_update
- jituan 服务层多处合并统计查询、批量预取 map
- rank 多处循环 N+1 改批量预取
- backend 多处循环内 count/create 改批量
- config/orders/merchant_ops 多处循环 N+1 改批量预取

其他改动：
- users/views/kefu.py 拆分为 kefu_base/kefu_dashou/kefu_orders/kefu_punishment/kefu_withdraw 5 个文件
- 删除遗留脚本 check_prod_uid.py / create_rbac_tables.sql

orders/views/boss_orders.py

@@ -422,11 +422,14 @@ class JiedanView(APIView):
                 # 7. 更新打手扩展表（如果有打手ID和分成）
                 if jiedan_dashou_id and dashou_fencheng > 0:
                     # 查询打手用户
-                    dashou_user = User.query.filter(UserUID=jiedan_dashou_id).first()
+                    dashou_user = User.query.filter(UserUID=jiedan_dashou_id).select_related('DashouProfile').first()
 
                     if dashou_user:
                         # 查询打手扩展表
-                        dashou_kuozhan = UserDashou.query.filter(user=dashou_user).first()
+                        try:
+                            dashou_kuozhan = dashou_user.DashouProfile
+                        except UserDashou.DoesNotExist:
+                            dashou_kuozhan = None
 
                         if dashou_kuozhan:
                             # 更新四个金额字段
@@ -585,7 +588,7 @@ class DingdanXiangqingView2(APIView):
             jiedan_time = ''
             tijiao_time = ''
             if jiedan_dashou_id:
-                dashou_user = User.query.filter(UserUID=jiedan_dashou_id).first()
+                dashou_user = User.query.filter(UserUID=jiedan_dashou_id).select_related('DashouProfile').first()
                 if dashou_user:
                     dashou_touxiang = dashou_user.Avatar or ''
                     try:
@@ -734,7 +737,7 @@ class JiedanView2(APIView):
 
                 # 9. 更新打手收益与状态
                 if jiedan_dashou_id and dashou_fencheng > 0:
-                    dashou_user = User.query.filter(UserUID=jiedan_dashou_id).first()
+                    dashou_user = User.query.filter(UserUID=jiedan_dashou_id).select_related('DashouProfile').first()
                     if dashou_user:
                         try:
                             dashou_ext = dashou_user.DashouProfile