feat: Integrate Unified Object Editor for Enhanced Dungeon Object Management

- Introduced ObjectEditorCard to consolidate object selection, emulator preview, and interaction controls into a single interface.
- Updated DungeonCanvasViewer to support object interaction context and handle mouse input for object selection and placement.
- Enhanced DungeonEditorV2 with new room graphics card for visualizing room graphics and improved layout for better user experience.
- Refactored existing components to accommodate the new unified editor, streamlining the workflow for managing dungeon objects.

src/app/editor/dungeon/dungeon_canvas_viewer.cc

@@ -103,6 +103,9 @@ void DungeonCanvasViewer::DrawDungeonCanvas(int room_id) {
   if (rooms_ && rom_->is_loaded()) {
     auto& room = (*rooms_)[room_id];
     
+    // Update object interaction context
+    object_interaction_.SetCurrentRoom(rooms_, room_id);
+    
     // Check if THIS ROOM's buffers need rendering (not global arena!)
     auto& bg1_bitmap = room.bg1_buffer().bitmap();
     bool needs_render = !bg1_bitmap.is_active() || bg1_bitmap.width() == 0;
@@ -139,6 +142,13 @@ void DungeonCanvasViewer::DrawDungeonCanvas(int room_id) {
       // Render sprites as simple 16x16 squares with labels
       RenderSprites(room);
     }
+    
+    // Handle object interaction if enabled
+    if (object_interaction_enabled_) {
+      object_interaction_.HandleCanvasMouseInput();
+      object_interaction_.CheckForObjectSelection();
+      object_interaction_.DrawSelectBox();
+    }
   }
   
   canvas_.DrawGrid();