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/Data/Texture.cs

@@ -142,6 +142,6 @@ public abstract unsafe class Texture : GraphicsResource
     public override void Dispose()
     {
         base.Dispose();
-        GraphicsPipeline.DescriptorAllocator.ReleaseBindless(_bindlessDescriptor);
+        GraphicsPipeline.DescriptorAllocator.Release(_bindlessDescriptor);
     }
 }