feat: implement descriptor heap with thread-safe allocation

D3D12 Resources:
- Add descriptor_handle struct with CPU/GPU handles
- Add descriptor_heap class for descriptor management
- Implement allocate() and free() methods
- Add mutex for thread-safe access
- Support all D3D12 descriptor heap types

D3D12 Core:
- Add device() function to expose main device
- Add release() template function for COM objects

Documentation:
- Add changelog for descriptor heap implementation
- Update D3D12 Wiki with descriptor heap section
- Mark descriptor heap task as completed

Engine/Graphics/Direct3D12/D3D12CommonHeader.h

@@ -16,6 +16,9 @@
 // 用于简化 COM 对象的生命周期管理
 #include <wrl.h>
 
+// 引入互斥锁头文件，用于保护资源的互斥锁
+#include <mutex>
+
 
 #pragma comment(lib, "dxgi.lib")
 #pragma comment(lib, "d3d12.lib")