docs: update RHI API docs

docs/api/rhi/pipeline-state/bind.md

@@ -0,0 +1,37 @@
+# RHIPipelineState::Bind
+
+```cpp
+virtual void Bind() = 0;
+```
+
+将管线状态绑定到渲染上下文。调用此方法后，该管线状态将成为当前活跃的渲染管线。
+
+**参数：** 无
+
+**返回：** 无
+
+**线程安全：** ❌
+
+**复杂度：** O(1)
+
+**示例：**
+
+```cpp
+#include "XCEngine/RHI/RHIPipelineState.h"
+
+class MyRenderer {
+    void DrawWithPipeline(RHIPipelineState* pipeline) {
+        pipeline->Bind();
+        
+        // 执行绘制操作
+        // Draw calls...
+        
+        pipeline->Unbind();
+    }
+};
+```
+
+## 相关文档
+
+- [RHIPipelineState](pipeline-state.md) - 返回类总览
+- [RHIPipelineState::Unbind](unbind.md) - 解绑管线状态