Uiux/booking abandonment banner

[Devadakene]

Closes #230

Summary

This PR implements the booking abandonment recovery banner as requested. When a user returns to the booking page after starting an incomplete checkout, they are now presented with a top-of-page banner. This banner offers the user three distinct actions: to resume where they left off, discard the draft, or view the details of their draft. This functionality aims to improve conversion and provides a smoother recovery experience.

Design Review Checklist

♿ Accessibility

• Contrast ratios meet WCAG 2.1 AA (4.5:1).
• Keyboard navigation is logical and focus rings are visible.
• Semantic HTML and ARIA labels are used correctly (includes a polite live region).

📱 Responsive

• Layout is mobile-first and works on all breakpoints.
• Above-the-fold content is optimized for laptop viewports.

⚙️ States & Tokens

• Loading, empty, and error states are handled.
• Design tokens (spacing, helper-text classes, indigo color palette) are followed.

Screenshots / Record

Nil

Testing

• npm run lint passes
• Manual keyboard/screen-reader test (Verified the banner's "Resume" action auto-focuses on load and the polite live region is properly announced).

[drips-wave]

@Devadakene Great news! 🎉 Based on an automated assessment of this PR, the linked Wave issue(s) no longer count against your application limits.

You can now already apply to more issues while waiting for a review of this PR. Keep up the great work! 🚀

Learn more about application limits