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/rhi/d3d12/screenshot/screenshot.md

@@ -0,0 +1,16 @@
+# D3D12Screenshot
+
+**命名空间**: `XCEngine::RHI`
+
+**描述**: D3D12 截图工具类，提供屏幕截图捕获功能。**所有方法均为静态方法**。
+
+## 公共方法
+
+| 方法 | 描述 |
+|------|------|
+| [`Capture`](capture.md) | 捕获截图 |
+| [`CopyToReadbackAndSave`](copy-to-readback-and-save.md) | 复制到回读缓冲并保存 |
+
+## 相关文档
+
+- [D3D12 后端总览](../../opengl/overview.md)