docs: update README with new Rust frontend and fix TypeScript version

- Updated README.md to reflect the addition of a native Rust frontend using egui
- Added setup instructions for the new rust-frontend directory
- Modified frontend package.json to downgrade TypeScript version from 5.3.3 to 4.9.5 due to conflicts
- Updated path references in documentation from ComfyUI-Rust/ to direct paths
- Reorganized project structure documentation to distinguish between original and new frontends

frontend/package.json

@@ -20,7 +20,7 @@
     "@types/node": "^20.11.0",
     "@types/react": "^18.2.45",
     "@types/react-dom": "^18.2.18",
-    "typescript": "^5.3.3"
+    "typescript": "^4.9.5"
   },
   "browserslist": {
     "production": [