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/initialize-from-existing.md

@@ -0,0 +1,35 @@
+# D3D12Buffer::InitializeFromExisting
+
+## 函数签名
+
+```cpp
+bool InitializeFromExisting(ID3D12Resource* resource)
+```
+
+## 中文描述
+
+从已存在的 D3D12 资源对象初始化缓冲区包装类，不分配新资源。
+
+## 参数
+
+| 参数 | 类型 | 描述 |
+|------|------|------|
+| `resource` | `ID3D12Resource*` | 已存在的 D3D12 资源指针 |
+
+## 返回值
+
+`bool` - 初始化是否成功
+
+## 复杂度
+
+O(1)
+
+## 示例
+
+```cpp
+ComPtr<ID3D12Resource> existingResource;
+device->CreateReservedResource(&desc, state, nullptr, IID_PPV_ARGS(&existingResource));
+
+D3D12Buffer buffer;
+buffer.InitializeFromExisting(existingResource.Get());
+```