fix: improve doc link navigation and tree display

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- Fix log file path for packaged app

docs/api/threading/task-group/waitfor.md

@@ -0,0 +1,39 @@
+# TaskGroup::WaitFor
+
+```cpp
+bool WaitFor(std::chrono::milliseconds timeout)
+```
+
+等待任务组中所有任务完成，可在超时后返回。
+
+**参数：**
+- `timeout` - 最大等待时间
+
+**返回：** `bool` - 所有任务在超时前完成返回 true，超时返回 false
+
+**复杂度：** O(n)
+
+**示例：**
+
+```cpp
+TaskGroup* group = TaskSystem::Get().CreateTaskGroup();
+
+for (int i = 0; i < 5; ++i) {
+    group->AddTask([i]() {
+        Thread::Sleep(i * 100);
+        printf("Task %d done\n", i);
+    });
+}
+
+if (group->WaitFor(std::chrono::seconds(1))) {
+    printf("All tasks completed within 1 second\n");
+} else {
+    printf("Timeout! Some tasks still running\n");
+    printf("Progress: %.1f%%\n", group->GetProgress() * 100.0f);
+}
+```
+
+## 相关文档
+
+- [TaskGroup 总览](task-group.md) - 返回类总览
+- [Wait](wait.md) - 无超时等待