修复前端测试偶发超时与异步清理

Direct 活动回合读取失败后的重试定时器随组件卸载清理，避免测试环境销毁后访问 window。

后台素材查询大量缩略图测试合并可见性触发，并补充独立超时预算。

创作首页活动图与资源卡预览调度重载用例分别补充独立超时预算。

清单快照测试补齐 Direct 活动回合 IPC mock，避免未预期命令进入重试。

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

@@ -38,6 +38,7 @@ vi.mock('../api/adminApiClient', () => ({
 
 interface MockIntersectionObserverController {
   enter: (target: Element) => void;
+  enterAll: (targets: Element[]) => void;
   isObserved: (target: Element) => boolean;
 }
 
@@ -106,6 +107,25 @@ function installIntersectionObserverMock(): MockIntersectionObserverController {
         );
       });
     },
+    enterAll(targets) {
+      act(() => {
+        for (const target of targets) {
+          const record = observed.get(target);
+          if (!record) {
+            throw new Error('目标缩略图尚未进入 IntersectionObserver');
+          }
+          record.callback(
+            [
+              {
+                isIntersecting: true,
+                target,
+              } as IntersectionObserverEntry,
+            ],
+            record.observer,
+          );
+        }
+      });
+    },
     isObserved(target) {
       return observed.has(target);
     },
@@ -753,10 +773,10 @@ test('后台素材查询为大量同时可见的缩略图持续错峰换签', as
   const thumbnails = entries.map((entry) =>
     thumbnailElementForLabel(entry.label),
   );
-  thumbnails.forEach((thumbnail) => {
+  for (const thumbnail of thumbnails) {
     expect(observer.isObserved(thumbnail)).toBe(true);
-    observer.enter(thumbnail);
-  });
+  }
+  observer.enterAll(thumbnails);
   await act(async () => {
     await Promise.resolve();
   });
@@ -776,7 +796,7 @@ test('后台素材查询为大量同时可见的缩略图持续错峰换签', as
     await vi.advanceTimersByTimeAsync(200);
   });
   expect(getAdminAssetReadUrl).toHaveBeenCalledTimes(105);
-});
+}, 10_000);
 
 test('后台素材查询读取更多后为新进入可视区域的素材换签', async () => {
   const observer = installIntersectionObserverMock();