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/rhi/d3d12/device/get-device.md

@@ -0,0 +1,19 @@
+# D3D12Device::GetDevice
+
+```cpp
+ID3D12Device* GetDevice() const
+```
+
+获取底层 D3D12 设备指针。
+
+**返回：** DirectX 12 设备指针
+
+**示例：**
+
+```cpp
+ID3D12Device* device = d3d12Device->GetDevice();
+```
+
+## 相关文档
+
+- [D3D12Device 总览](device.md) - 返回类总览