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/AgentNodeStoreRequest.php

@@ -31,7 +31,7 @@ final class AgentNodeStoreRequest extends ApiFormRequest
             'name' => ['required', 'string', 'max:128'],
             'username' => ['sometimes', 'nullable', ...$this->adminOperatorUsernameRules(required: false), Rule::unique('admin_users', 'username')],
             'email' => ['nullable', 'email', 'max:255', Rule::unique('admin_users', 'email')],
-            'password' => ['required', 'string', 'min:8', 'max:128'],
+            'password' => ['required', 'string', 'min:6', 'max:128'],
             'status' => ['sometimes', 'integer', 'in:0,1'],
             ...$this->agentProfileFieldRules(),
         ];