- Implemented `Favorite` model with unique user-item constraint and timestamped records
- Added `favorites:index` and `favorites:toggle` views with AJAX support for toggling favorites
- Built templates and front-end assets for the favorites page and integration with item grids
- Extended header with favorites link and dynamic counter
- Added tests covering models, views, and templates for the favorites functionality
- Updated admin to enable management of favorites via Django admin interface
