Add Comprehensive Dungeon Editor Design Plan

- Introduced a detailed design plan document for the Yaze Dungeon Editor, outlining the current architecture, main components, and core systems.
- Documented identified issues and applied fixes, including crash prevention and UI simplification, along with a roadmap for future development phases.
- Enhanced clarity on the implementation guidelines, testing strategies, and performance considerations to support ongoing development efforts.
- Established a structured approach for new developers to understand the codebase and contribute effectively to the project.

src/app/editor/dungeon/dungeon_canvas_viewer.cc

@@ -65,6 +65,10 @@ void DungeonCanvasViewer::DrawDungeonTabView() {
   Separator();
 }
 
+void DungeonCanvasViewer::Draw(int room_id) {
+  DrawDungeonCanvas(room_id);
+}
+
 void DungeonCanvasViewer::DrawDungeonCanvas(int room_id) {
   // Validate room_id and ROM
   if (room_id < 0 || room_id >= 128) {