- Replace customers.html with design system clientes page, add slide panel + wire to customers.js
- Replace inventory.html with design system inventario page, load inventory.js
- Add empty state component to catalog product grid (hidden, shown when no results)
- Add offline banner HTML/CSS to all three pages
- Create offline-banner.js: listens online/offline events, auto-dismisses restored banner after 3s
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
