docs: update RHI API docs

docs/api/rhi/d3d12/command-list/get-resource-state.md

@@ -9,10 +9,22 @@ ResourceStates GetResourceState(ID3D12Resource* resource) const;
 **参数：**
 - `resource` - D3D12 资源指针
 
-**返回：** 资源当前状态
+**返回值：** 资源当前状态，如果资源未被跟踪则返回 `ResourceStates::Common`
 
 **复杂度：** O(1)
 
+**示例：**
+
+```cpp
+ID3D12Resource* resource = /* 获取资源 */;
+ResourceStates state = cmdList.GetResourceState(resource);
+if (state == ResourceStates::RenderTarget) {
+    // 资源当前为渲染目标状态
+}
+```
+
 ## 相关文档
 
 - [D3D12CommandList 总览](command-list.md) - 返回类总览
+- [TrackResource](track-resource.md) - 跟踪资源
+- [TransitionBarrier](transition-barrier.md) - 资源状态转换