feat: 后台添加商家 + 龙先生 lsx 俱乐部/邀请链种子

支持客服按用户UID开通商家（分俱乐部校验）；新增 seed_club_lsx、seed_lsx_invite_data。

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

backend/view.py

@@ -35,6 +35,7 @@ from .views.roles import (
 from .views.kefu import (
     KefuGetDashouListView, KefuGetDashouDetailView, KefuUpdateDashouView,
     KefuGetShangjiaListView, KefuGetShangjiaDetailView, KefuUpdateShangjiaView,
+    KefuAddShangjiaView,
     KefuChatPermissionsView,
     DashouGiftHuiyuanSaveView, DashouGiftHuiyuanRemoveView,
 )
@@ -100,6 +101,7 @@ __all__ = [
     'KefuGetDashouListView', 'KefuGetDashouDetailView', 'KefuUpdateDashouView',
     'DashouGiftHuiyuanSaveView', 'DashouGiftHuiyuanRemoveView',
     'KefuGetShangjiaListView', 'KefuGetShangjiaDetailView', 'KefuUpdateShangjiaView',
+    'KefuAddShangjiaView',
     'KefuChatPermissionsView',
     # products
     'GetProductBaseDataView', 'GetProductListView', 'SaveProductOrderView',