feat: implement command queue with multi-frame buffering

D3D12 Core:
- Add d3d12_command class for command queue management
- Support Direct/Compute/Copy command queue types
- Implement multi-frame buffering (frame_buffer_count=3)
- Add begin_frame/end_frame rendering cycle
- Add NAME_D3D12_OBJECT_INDEXED macro

Platform Interface:
- Add render function pointer to platform_interface
- Implement render() in Renderer

Documentation:
- Add changelog for command queue implementation
- Update D3D12 Wiki with multi-frame buffering section
- Mark command queue task as completed

EngineTest/TestRenderer.cpp

@@ -11,7 +11,7 @@
 #include <fstream>
 
 
-#if TEST_RENDERER
+#ifdef TEST_RENDERER
 using namespace XEngine;
 
 graphics::render_surface _surfaces[4];
@@ -108,4 +108,4 @@ engine_test::shutdown()
 
 	return true;
 }
-#endif
+#endif // TEST_RENDERER