docs: update resources API docs

docs/api/resources/mesh/get-vertex-count.md

@@ -0,0 +1,34 @@
+# Mesh::GetVertexCount
+
+```cpp
+Core::uint32 GetVertexCount() const;
+```
+
+获取网格的顶点数量。
+
+**参数：** 无
+
+**返回：** `Core::uint32` - 顶点数量
+
+**异常：** 无
+
+**线程安全：** ✅
+
+**复杂度：** O(1)
+
+**示例：**
+
+```cpp
+#include "XCEngine/Resources/Mesh.h"
+
+using namespace XCEngine::Resources;
+
+Mesh mesh;
+mesh.SetVertexData(...);
+
+uint32_t vertexCount = mesh.GetVertexCount();
+```
+
+## 相关文档
+
+- [类总览](mesh.md) - 返回类总览