fix: improve doc link navigation and tree display

- Fix link resolution with proper relative/absolute path handling
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- Fix log file path for packaged app

docs/api/math/matrix4/lookat.md

@@ -0,0 +1,22 @@
+# Matrix4::LookAt
+
+```cpp
+static Matrix4 LookAt(const Vector3& eye, const Vector3& target, const Vector3& up)
+```
+
+创建视图矩阵（观察矩阵）。
+
+**参数：**
+- `eye` - 相机位置
+- `target` - 观察目标点
+- `up` - 世界空间中的上方向
+
+**返回：** `Matrix4` - 视图矩阵
+
+**复杂度：** O(1)
+
+**示例：**
+
+```cpp
+Matrix4 view = Matrix4::LookAt(cameraPos, target, Vector3::Up());
+```