Render graph: native pass merging & heap-based aliasing

Major architecture upgrade:
- Add native render pass merging (hardware pass grouping, load/store op inference)
- Implement heap-based aliasing for textures & buffers (D3D12-style)
- Unify resource model: buffers and textures in one registry
- Extend builder API for buffer creation/usage, access flags, hints
- Improve barrier/state tracking (buffer hints, indirect argument state)
- Update caching, hashing, and debug output for new model
- Add enums/structs: AttachmentLoadOp, StoreOp, BufferHint, etc.
- D3D12 backend: support named resources, temp upload buffers, correct heap usage
- Update docs, benchmarks, and project files for new features

Brings render graph closer to AAA engine standards, enabling efficient memory usage, lower driver overhead, and a more flexible API.

Ghost.Graphics/RHI/Common.cs

@@ -224,6 +224,22 @@ public struct PassRenderTargetDesc
         get; set;
     }
 
+    /// <summary>
+    /// Specifies how to load the render target at the start of the render pass.
+    /// </summary>
+    public AttachmentLoadOp LoadOp
+    {
+        get; set;
+    }
+
+    /// <summary>
+    /// Specifies how to store the render target at the end of the render pass.
+    /// </summary>
+    public AttachmentStoreOp StoreOp
+    {
+        get; set;
+    }
+
 }
 
 public struct PassDepthStencilDesc
@@ -243,6 +259,38 @@ public struct PassDepthStencilDesc
         get; set;
     }
 
+    /// <summary>
+    /// Specifies how to load the depth buffer at the start of the render pass.
+    /// </summary>
+    public AttachmentLoadOp DepthLoadOp
+    {
+        get; set;
+    }
+
+    /// <summary>
+    /// Specifies how to store the depth buffer at the end of the render pass.
+    /// </summary>
+    public AttachmentStoreOp DepthStoreOp
+    {
+        get; set;
+    }
+
+    /// <summary>
+    /// Specifies how to load the stencil buffer at the start of the render pass.
+    /// </summary>
+    public AttachmentLoadOp StencilLoadOp
+    {
+        get; set;
+    }
+
+    /// <summary>
+    /// Specifies how to store the stencil buffer at the end of the render pass.
+    /// </summary>
+    public AttachmentStoreOp StencilStoreOp
+    {
+        get; set;
+    }
+
 }
 
 
@@ -704,7 +752,7 @@ public struct SwapChainTarget
         {
             Type = SwapChainTargetType.WindowHandle,
             WindowHandle = hwnd,
-            CompositionSurface = null
+            CompositionSurface = 0
         };
     }
 
@@ -878,3 +926,42 @@ public enum ComparisonFunction
     GreaterEqual,
     Always
 }
+
+/// <summary>
+/// Specifies how to load attachment contents at the start of a render pass.
+/// </summary>
+public enum AttachmentLoadOp
+{
+    /// <summary>
+    /// Load existing contents from memory. Use when you need to preserve previous data.
+    /// </summary>
+    Load,
+
+    /// <summary>
+    /// Clear the attachment to a specified value. Use when you want to start with a clean slate.
+    /// </summary>
+    Clear,
+
+    /// <summary>
+    /// Don't care about previous contents. Use when you'll overwrite all pixels (fullscreen pass).
+    /// On tile-based deferred renderers (TBDR), this can save significant memory bandwidth.
+    /// </summary>
+    DontCare
+}
+
+/// <summary>
+/// Specifies how to store attachment contents at the end of a render pass.
+/// </summary>
+public enum AttachmentStoreOp
+{
+    /// <summary>
+    /// Store the contents to memory for later use.
+    /// </summary>
+    Store,
+
+    /// <summary>
+    /// Discard the contents (not needed after this pass).
+    /// On tile-based deferred renderers (TBDR), this can save significant memory bandwidth.
+    /// </summary>
+    DontCare
+}