Refactor GPU resource management and rendering pipeline

- Introduced `Handle<T>` and `Identifier<T>` for lightweight, strongly-typed resource identifiers.
- Replaced `BitSet` with `UnsafeBitSet` for improved performance and memory safety.
- Refactored `Mesh` and `Material` into `MeshClass` and `MaterialClass` for better GPU resource handling.
- Added `D3D12ResourceDatabase` to centralize GPU resource tracking and lifecycle management.
- Updated `D3D12ShaderCompiler` to load shaders from disk and dynamically populate constant buffers and textures.
- Enhanced `ICommandBuffer` with new upload operations for buffers and textures.
- Refactored `Vertex` struct for simplified memory layout and better performance.
- Updated `MeshBuilder` and rendering logic to align with new resource and shader structures.
- Added `BindlessDescriptor` support to `TextureHandle` and `BufferHandle`.
- Removed unused classes and performed general cleanup.
- Updated unit tests and demos to reflect the new architecture.

Ghost.UnitTest/UnitTestApp.xaml

@@ -8,7 +8,7 @@
         <ResourceDictionary>
             <ResourceDictionary.MergedDictionaries>
                 <XamlControlsResources xmlns="using:Microsoft.UI.Xaml.Controls" />
-                <!--  Other merged dictionaries here  -->
+                <ResourceDictionary Source="ms-appx:///Microsoft.UI.Xaml/DensityStyles/Compact.xaml" />
             </ResourceDictionary.MergedDictionaries>
             <!--  Other app resources here  -->
         </ResourceDictionary>

Ghost.UnitTest/Windows/GraphicsTestWindow.xaml.cs

@@ -34,7 +34,7 @@ public sealed partial class GraphicsTestWindow : Window
         _renderSystem = new (GraphicsAPI.Direct3D12);
         _renderer = _renderSystem.CreateRenderer();
 
-        _swapChain = _renderSystem.GraphicsEngine.Device.CreateSwapChain(new SwapChainDesc((uint)AppWindow.Size.Width, (uint)AppWindow.Size.Height, SwapChainTarget.FromCompositionSurface(Panel)));
+        _swapChain = _renderSystem.GraphicsEngine.CreateSwapChain(new SwapChainDesc((uint)AppWindow.Size.Width, (uint)AppWindow.Size.Height, SwapChainTarget.FromCompositionSurface(Panel)));
         _renderer.SetSwapChain(_swapChain);
 
         CompositionTarget.Rendering += OnRendering;