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/vector2/left.md

@@ -0,0 +1,17 @@
+# Vector2::Left
+
+```cpp
+static Vector2 Left()
+```
+
+返回左方向向量 (-1, 0)。
+
+**返回：** `Vector2` - 值为 (-1, 0) 的向量
+
+**复杂度：** O(1)
+
+**示例：**
+
+```cpp
+Vector2 left = Vector2::Left();
+```