Refactor descriptor handling and shader compilation

Refactored descriptor allocation and release logic by introducing `IDescriptorAllocator` and replacing `DescriptorHeapAllocator` with `D3D12DescriptorHeap`. Updated descriptor structs to include validation properties and improved memory management with `ReadOnlySpan`.

Enhanced shader compilation by introducing `ShaderStage` and `CompilerVersion` enums, enabling more flexible and maintainable shader handling.

Refactored `Mesh` to use `IBuffer` for vertex and index buffers, added bindless descriptor support, and improved resource cleanup.

Updated `RenderSystem` and other components for better initialization, error handling, and disposal logic. General improvements to code readability and maintainability.

Ghost.Graphics/D3D12/Renderer.cs

@@ -64,7 +64,7 @@ internal unsafe class Renderer
             commandAllocator.Dispose();
             commandList.Dispose();
             backBuffer.Dispose();
-            GraphicsPipeline.DescriptorAllocator.ReleaseRTV(rtvDescriptor);
+            GraphicsPipeline.DescriptorAllocator.Release(rtvDescriptor);
         }
     }
 
@@ -226,7 +226,7 @@ internal unsafe class Renderer
             if (frameResource.backBuffer.Get() is not null)
             {
                 var c = frameResource.backBuffer.Reset();
-                GraphicsPipeline.DescriptorAllocator.ReleaseRTV(frameResource.rtvDescriptor);
+                GraphicsPipeline.DescriptorAllocator.Release(frameResource.rtvDescriptor);
             }
 
             frameResource.fenceValue = _frameResources[_backBufferIndex].fenceValue;