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

App/editor/Editor.h

@@ -29,6 +29,8 @@ class InspectorPanel;
 class ViewportPanel;
 class StatsPanel;
 class AssetBrowserPanel;
+class MaterialEditorPanel;
+class ControllerEditorPanel;
 
 class Editor {
 public:
@@ -108,6 +110,8 @@ private:
     std::unique_ptr<ViewportPanel> m_Viewport;
     std::unique_ptr<StatsPanel> m_Stats;
     std::unique_ptr<AssetBrowserPanel> m_AssetBrowser;
+    std::unique_ptr<MaterialEditorPanel> m_MaterialEditor;
+    std::unique_ptr<ControllerEditorPanel> m_ControllerEditor;
 
     entt::entity m_Selected{entt::null};
 
@@ -117,6 +121,7 @@ private:
     bool m_ShowViewport = true;
     bool m_ShowStats = true;
     bool m_ShowAssetBrowser = true;
+    bool m_ShowMaterialEditor = true;
 
     // 默认布局只建一次（imgui.ini 已有布局则跳过）
     bool m_LayoutBuilt = false;