mnerv
70315a3fd1
Add multi-cart UI, image caching, copy/paste, and mobile layout fixes
- Multi-cart system with create, rename, delete, import/export
- Sections with copy/paste items via clipboard JSON
- IndexedDB image cache with deduplication and unused-image pruning
- Migrate existing localStorage base64 images to IndexedDB on load
- Mobile-responsive header and cart bar
- Template row with pill buttons replacing dropdown select
- Cart rename via double-click inline edit
- Storage quota error handling with user-facing banner
- Updated README and page title/description
