feat(render): refactor pipeline & shader system for DX12 WG

Major refactor of render pipeline and shader system:
- Replaced legacy shader properties with source generator and attribute-based HLSL struct generation.
- Introduced ShaderPropertiesRegistry for runtime property layout/code registration.
- Added modular IRenderPipeline, IRenderPipelineSettings, and IRenderPayload interfaces.
- Implemented GhostRenderPipeline and ECS-driven GPUScene management.
- Added experimental DirectX 12 Work Graph support.
- Refactored shader compilation, variant hashing, and caching.
- Updated APIs for consistency and improved codegen for registration.

These changes modernize the rendering infrastructure for advanced features like work graphs and dynamic pipelines.

BREAKING CHANGE: Shader DSL, pipeline, and property APIs have changed. Existing shaders and pipeline integrations must be updated.

src/Runtime/Ghost.Engine/Systems/AddGPUInstanceSystem.cs

@@ -0,0 +1,52 @@
+using Ghost.Core;
+using Ghost.Engine.Components;
+using Ghost.Engine.RenderPipeline;
+using Ghost.Entities;
+using Ghost.Graphics;
+using Misaki.HighPerformance.Utilities;
+
+namespace Ghost.Engine.Systems;
+
+[RenderPipelineSystem<GhostRenderPipelineSettings>]
+internal class AddGPUInstanceSystem : SystemBase
+{
+    private RenderSystem _renderSystem = null!;
+
+    private Identifier<EntityQuery> _meshInstanceQueryID;
+
+    protected override void OnInitialize(ref readonly SystemAPI systemAPI)
+    {
+        _renderSystem = systemAPI.World.GetService<RenderSystem>();
+
+        _meshInstanceQueryID = QueryBuilder.Create()
+            .WithAll<MeshInstance, LocalToWorld>()
+            .WithAbsent<GPUInstanceRef>()
+            .Build(systemAPI.World, true);
+
+        RequireQueryForUpdate(_meshInstanceQueryID);
+    }
+
+    protected override void OnUpdate(ref readonly SystemAPI systemAPI)
+    {
+        var payload = (GhostRenderPayload)_renderSystem.GetCurrentFramePayload();
+
+        ref var meshInstanceQuery = ref systemAPI.World.ComponentManager.GetEntityQueryReference(_meshInstanceQueryID);
+
+        foreach (var chunk in meshInstanceQuery.GetChunkIterator())
+        {
+            var meshInstances = chunk.GetComponentData<MeshInstance>();
+            var localToWorlds = chunk.GetComponentData<LocalToWorld>();
+            var entities = chunk.GetEntities();
+
+            for (var i = 0; i < chunk.EntityCount; i++)
+            {
+                ref readonly var meshInstance = ref meshInstances.GetElementUnsafe(i);
+                var localToWorld = localToWorlds.GetElementUnsafe(i);
+                var entity = entities.GetElementUnsafe(i);
+
+                var index = payload.AddInstance(localToWorld.matrix, in meshInstance);
+                systemAPI.World.EntityCommandBuffer.AddComponent(entity, new GPUInstanceRef { gpuSceneIndex = index });
+            }
+        }
+    }
+}