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/RHI/ICommandQueue.cs

@@ -1,7 +1,7 @@
 namespace Ghost.Graphics.RHI;
 
 /// <summary>
-/// D3D12-style command queue interface
+/// Command queue interface
 /// </summary>
 public interface ICommandQueue : IDisposable
 {
@@ -46,7 +46,7 @@ public interface ICommandQueue : IDisposable
 }
 
 /// <summary>
-/// Command queue types matching D3D12
+/// Command queue types
 /// </summary>
 public enum CommandQueueType
 {