fix: improve doc link navigation and tree display

- Fix link resolution with proper relative/absolute path handling
- Improve link styling with underline decoration
- Hide leaf nodes from tree, only show directories
- Fix log file path for packaged app

docs/api/resources/asyncloader/getprogress.md

@@ -0,0 +1,24 @@
+# AsyncLoader::GetProgress
+
+```cpp
+float GetProgress() const
+```
+
+获取整体加载进度。返回已完成加载数与总请求数的比值，范围 0.0f ~ 1.0f。
+
+**参数：** 无
+
+**返回：** 加载进度（0.0f ~ 1.0f）
+
+**复杂度：** O(1)
+
+**示例：**
+
+```cpp
+float progress = AsyncLoader::Get().GetProgress();
+printf("Loading: %.1f%%\n", progress * 100.0f);
+```
+
+## 相关文档
+
+- [AsyncLoader 总览](asyncloader.md) - 返回类总览