fix(ux): replace native confirm() dialogs, add undo-toast, fix prefers-reduced-motion
- Replace all 13 native confirm() calls with confirmModal() across 7 page modules
- Add confirmModal() to modal.js (Promise-based, danger variant, focus management)
- Fix double-confirm bug in contacts.js and budget.js (modal + deleteContact/deleteEntry)
- Extend showToast() with onUndo callback and max-3-toast limit
- Implement optimistic undo-toast (4s window) for shopping item and bulk-checked delete
- Add prefers-reduced-motion guard to btnSuccess() and btnError() in modal.js
- Add btn--error-static CSS class as motion-reduced fallback for btnError()
- Add toast__undo button styles to layout.css
- Add common.confirm and common.undo i18n keys (de, en, it, sv)
- Add shopping.itemDeletedToast i18n key (de, en, it, sv)
Ulas
44e5a879b9