feat: add badge collection examples and update release notes for vers…

…ion 2.0.3

Add badge collection feature with documentation and routes

- Implement BadgeCollectionController to render multiple badges as a single SVG.
- Create routes for badge collection and integrate with existing route registration.
- Update API documentation for badge collection endpoint.
- Add examples and error handling for badge collection requests.
- Bump version to 2.0.1 in package.json.