Add animation controller system, material assets and skeleton visualization

- .animctrl state machine asset (params/transitions/blend trees, 1D+2D
  directional blending) with Unity Animator-style editor panel: state
  list, transitions, params, directional pad preview driving live
  CrossFade on the selected entity
- Split animation evaluation out of SceneRenderer into
  AnimationSystem/AnimationEvaluator; skin palettes with rest-pose
  fallback and blend-weight epsilon filtering
- MaterialAsset (.material) with reload-safe preview tile pool
  (DropMaterial clears dirty refs before instance destruction)
- EditorGizmoPass skeleton wires + viewport joint overlay; camera
  projection rework (baked Vulkan Y-flip, ortho support)
- Editor/game build split via HELLOVULKAN_EDITOR option

Engine/src/Renderer/Passes/ImGuiPass.cpp

@@ -48,7 +48,14 @@ namespace Engine::Passes
           // 场景纹理在本 pass 内被 ImGui::Image 的描述符采样：声明读让 RG
           // 补 ColorAttachment→ShaderRead barrier，并推导 eSampled usage
           .Read(m_PresentTarget, RG::ResourceUse::ShaderRead,
-                vk::ShaderStageFlagBits::eFragment);
+                vk::ShaderStageFlagBits::eFragment)
+#ifdef HELLO_EDITOR
+          // 材质球预览 atlas 同理（材质槽行的 ImGui::Image 采样）；
+          // game 构建不声明（atlas 不存在）
+          .Read(m_PreviewAtlas, RG::ResourceUse::ShaderRead,
+                vk::ShaderStageFlagBits::eFragment)
+#endif
+          ;
     }
 
 } // namespace Engine::Passes