完善客户端发布渠道并接入模板库灰度

区分发布渠道与系统，支持 dev、release 和自定义渠道
允许网站通过服务端配置选择客户端下载检测渠道
接入模板库灰度权限并阻断退出和切号后的异步操作
补齐发布、下载、灰度与会话竞态测试及当前规范

apps/admin-web/src/pages/AdminGrayReleaseConfigPage.test.tsx

@@ -154,6 +154,27 @@ test('灰度发布页可通过功能入口生成画布 Agent Gate Key', async ()
   );
 });
 
+test('灰度发布页可选择模板库并默认启用零比例灰度', async () => {
+  const user = userEvent.setup();
+  render(
+    <AdminGrayReleaseConfigPage token="admin-token" onUnauthorized={vi.fn()} />,
+  );
+  await screen.findByRole('button', { name: 'editor.new-toolbar' });
+  await user.selectOptions(screen.getByLabelText('Gate Key 前缀'), ['agc']);
+  expect((screen.getByLabelText('Gate Key') as HTMLInputElement).value).toBe(
+    'agc:template-library',
+  );
+  expect(
+    (screen.getByLabelText('Gate Key 目标') as HTMLSelectElement).value,
+  ).toBe('template-library');
+  expect((screen.getByLabelText('启用') as HTMLInputElement).checked).toBe(
+    true,
+  );
+  expect((screen.getByLabelText('灰度比例') as HTMLInputElement).value).toBe(
+    '0',
+  );
+});
+
 test('灰度发布页保存时转换数组和百分比', async () => {
   const user = userEvent.setup();
   vi.mocked(upsertAdminFeatureGateConfig).mockResolvedValueOnce({

apps/admin-web/src/pages/AdminGrayReleaseConfigPage.tsx

@@ -27,9 +27,17 @@ interface GateTargetOption {
 
 const GATE_PREFIX_LABELS: Record<string, string> = {
   'image-editor': '画布',
+  agc: '客户端',
 };
 
 const FIXED_GATE_TARGETS: GateTargetOption[] = [
+  {
+    prefix: 'agc',
+    suffix: 'template-library',
+    key: 'agc:template-library',
+    label: '模板库',
+    description: '客户端模板库灰度',
+  },
   {
     prefix: 'image-editor',
     suffix: 'agent-sidebar',
@@ -180,7 +188,7 @@ export function AdminGrayReleaseConfigPage({
     setSelectedGateKey('');
     setGatePrefix(option.prefix);
     setGateKey(option.key);
-    setEnabled(false);
+    setEnabled(option.key === 'agc:template-library');
     setRolloutPercent('0');
     setAllowUserIds('');
     setAllowUserTags('');