feat(admin): 密码校验统一与后台 API/设置增强

- 管理端账号/代理/站点等密码最短长度统一为 6 位
- LotterySettings、审计日志展示、币种与报表接口等小修复
- 补充设置批量更新、注单、校验错误等相关测试

app/Http/Requests/Admin/AdminIntegrationSiteStoreRequest.php

@@ -33,7 +33,7 @@ final class AdminIntegrationSiteStoreRequest extends ApiFormRequest
             'admin_account' => ['required', 'array'],
             'admin_account.username' => ['required', 'string', 'max:64', Rule::unique('admin_users', 'username')],
             'admin_account.nickname' => ['required', 'string', 'max:64'],
-            'admin_account.password' => ['required', 'string', 'min:8', 'max:255'],
+            'admin_account.password' => ['required', 'string', 'min:6', 'max:255'],
             'admin_account.email' => ['nullable', 'email', 'max:255'],
         ];
     }