refactor(editor): Phase 1 architecture refactoring

- Decouple Panel from Core::Layer (P0 issue resolved)
- Add EventBus with type-safe event system
- Add ISelectionManager interface with SelectionManagerImpl
- Add IEditorContext for dependency injection
- Update EditorLayer to use new architecture
- Update Application to create and inject EditorContext

New files:
- editor/src/Core/EventBus.h
- editor/src/Core/EditorEvents.h
- editor/src/Core/ISelectionManager.h
- editor/src/Core/SelectionManagerImpl.h
- editor/src/Core/IEditorContext.h
- editor/src/Core/EditorContextImpl.h

This enables future improvements: Undo/Redo, serialization, component extensibility.

editor/src/Layers/EditorLayer.cpp

@@ -6,8 +6,8 @@
 #include "panels/InspectorPanel.h"
 #include "panels/ConsolePanel.h"
 #include "panels/ProjectPanel.h"
-#include "Managers/SelectionManager.h"
-#include "Managers/SceneManager.h"
+#include "Core/IEditorContext.h"
+#include "Core/EditorContextImpl.h"
 #include <imgui.h>
 #include <imgui_internal.h>
 
@@ -16,7 +16,15 @@ namespace Editor {
 
 EditorLayer::EditorLayer() : Layer("Editor") {}
 
+void EditorLayer::SetContext(std::shared_ptr<IEditorContext> context) {
+    m_context = context;
+}
+
 void EditorLayer::onAttach() {
+    if (!m_context) {
+        m_context = std::make_shared<EditorContextImpl>();
+    }
+    
     m_menuBar = std::make_unique<MenuBar>();
     m_hierarchyPanel = std::make_unique<HierarchyPanel>();
     m_sceneViewPanel = std::make_unique<SceneViewPanel>();
@@ -25,14 +33,25 @@ void EditorLayer::onAttach() {
     m_consolePanel = std::make_unique<ConsolePanel>();
     m_projectPanel = std::make_unique<ProjectPanel>();
     
-    m_projectPanel->Initialize(m_projectPath);
+    m_menuBar->OnAttach();
+    m_hierarchyPanel->OnAttach();
+    m_sceneViewPanel->OnAttach();
+    m_gameViewPanel->OnAttach();
+    m_inspectorPanel->OnAttach();
+    m_consolePanel->OnAttach();
+    m_projectPanel->OnAttach();
     
-    auto& selection = SelectionManager::Get();
-    selection.OnSelectionChanged.Subscribe([](uint64_t id) {
-    });
+    m_projectPanel->Initialize(m_context->GetProjectPath());
 }
 
 void EditorLayer::onDetach() {
+    m_menuBar->OnDetach();
+    m_hierarchyPanel->OnDetach();
+    m_sceneViewPanel->OnDetach();
+    m_gameViewPanel->OnDetach();
+    m_inspectorPanel->OnDetach();
+    m_consolePanel->OnDetach();
+    m_projectPanel->OnDetach();
 }
 
 void EditorLayer::onUpdate(float dt) {
@@ -58,10 +77,6 @@ void EditorLayer::onImGuiRender() {
     renderAllPanels();
 }
 
-void EditorLayer::SetProjectPath(const std::string& path) {
-    m_projectPath = path;
-}
-
 void EditorLayer::setupDockspace() {
     static ImGuiDockNodeFlags dockspaceFlags = ImGuiDockNodeFlags_NoWindowMenuButton;