refactor: rename ui_editor to editor for consistency

editor/src/Managers/SelectionManager.h

@@ -0,0 +1,39 @@
+#pragma once
+
+#include "Core/GameObject.h"
+#include <unordered_set>
+
+#include <XCEngine/Core/Event.h>
+
+namespace UI {
+
+class SelectionManager {
+public:
+    static SelectionManager& Get() {
+        static SelectionManager instance;
+        return instance;
+    }
+    
+    EntityID GetSelectedEntity() const { return m_selectedEntity; }
+    
+    void SetSelectedEntity(EntityID id) {
+        m_selectedEntity = id;
+        OnSelectionChanged.Invoke(id);
+    }
+    
+    void ClearSelection() {
+        SetSelectedEntity(INVALID_ENTITY_ID);
+    }
+    
+    bool IsSelected(EntityID id) const {
+        return m_selectedEntity == id;
+    }
+    
+    XCEngine::Core::Event<EntityID> OnSelectionChanged;
+    
+private:
+    SelectionManager() = default;
+    EntityID m_selectedEntity = INVALID_ENTITY_ID;
+};
+
+}