后端与全仓代码质量清理（golangci 扩展集 · 测试质量 · 并发安全 · 文档同步）

代码质量全量清理，零行为变化：golangci 扩展集 13 类 linter（gosec/modernize/perfsprint/canonicalheader/usestdlibvars/wastedassign/intrange/errorlint/forcetypeassert/recvcheck/exhaustive/unparam）全量修复，测试代码质量（testifylint/thelper/usetesting）25→0，frpc 进程生命周期真 bug（进程组击杀）、全仓 go test -race 6 类数据竞争（含 1 个生产竞争）、SPDX license 头补齐 131 文件、前端测试套件 next-intl 迁移后 44 失败→全绿、过期 swagger 文档重新生成、pnpm-workspace 构建审批。

Experiments: #2-#17, #18, #20, #21, #23
Metric: total_issues 108 → 8 (-92.6%)

frontend/tests/cloudflare/sync-tasks-panel.test.tsx

@@ -5,6 +5,8 @@ import { beforeEach, describe, expect, it, vi } from 'vitest';
 import { SyncTasksPanel } from '@/app/(main)/cloudflare/components/sync-tasks-panel';
 import { AdminTaskService } from '@/lib/services/admin';
 import type { TaskExecution } from '@/lib/services/admin';
+import { NextIntlClientProvider } from 'next-intl';
+import zhCN from '@/messages/zh-CN.json';
 
 vi.mock('@/lib/services/admin', async (importOriginal) => {
   const actual = await importOriginal<typeof import('@/lib/services/admin')>();
@@ -24,9 +26,11 @@ function renderPanel() {
     defaultOptions: { queries: { retry: false, gcTime: 0 } },
   });
   render(
-    <QueryClientProvider client={client}>
-      <SyncTasksPanel />
-    </QueryClientProvider>,
+    <NextIntlClientProvider locale='zh-CN' messages={zhCN} timeZone='Asia/Shanghai'>
+      <QueryClientProvider client={client}>
+        <SyncTasksPanel />
+      </QueryClientProvider>
+    </NextIntlClientProvider>,
   );
 }