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/math/rect/viewport-getrect.md

@@ -0,0 +1,18 @@
+# Viewport::GetRect
+
+```cpp
+Rect GetRect() const
+```
+
+将视口转换为 Rect。
+
+**返回：** `Rect` - 对应的矩形 (x, y, width, height)，不包含深度范围
+
+**复杂度：** O(1)
+
+**示例：**
+
+```cpp
+Viewport viewport(0, 0, 1920, 1080, 0.0f, 1.0f);
+Rect rect = viewport.GetRect();  // (0, 0, 1920, 1080)
+```