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/material/setshader.md

@@ -0,0 +1,26 @@
+# Material::SetShader
+
+```cpp
+void SetShader(const ResourceHandle<Shader>& shader)
+```
+
+设置材质使用的着色器。
+
+**参数：**
+- `shader` - 着色器资源句柄
+
+**返回：** 无
+
+**复杂度：** O(1)
+
+**示例：**
+
+```cpp
+ResourceHandle<Shader> vs = ResourceManager::Get().Load<Shader>("shaders/vertex.glsl");
+ResourceHandle<Shader> fs = ResourceManager::Get().Load<Shader>("shaders/fragment.glsl");
+mat->SetShader(vs);
+```
+
+## 相关文档
+
+- [Material 总览](material.md) - 返回类总览