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/buffer/unmap.md

@@ -0,0 +1,15 @@
+# D3D12Buffer::Unmap
+
+## 函数签名
+
+```cpp
+void Unmap() override
+```
+
+## 中文描述
+
+解除缓冲区内存映射。
+
+## 复杂度
+
+O(1)