feat(frontend-design): empty state illustration style + copy guidelines

[Dayz-tech-co]

Summary

• redesign the dashboard empty-state experience around clarity, trust, and fast scanning
• add reusable empty-state building blocks for illustration, status chips, and CTA treatment
• add route-level loading and error states for the dashboard
• document copy and illustration guidelines for future empty-state work

What changed

• replaced the placeholder dashboard panel with a structured design-first state system
• introduced reusable components for:
  • dashboard shell
  • empty state card
  • abstract empty state illustration
  • button link
  • status chip
• added responsive loading and error screens under the App Router dashboard route
• updated global visual tokens and focus styles to support the new UI treatment
• removed remote Google font dependency so production builds work reliably without font fetch failures

UX notes

• empty states now explain what is missing, why it matters, and what the next action should be
• wallet copy is intentionally trust-first and avoids sounding like a hard gate
• booking progress is framed as a guided flow so users can understand setup at a glance

Testing

• npm run lint
• npm run build

Accessibility

• keyboard-visible focus states
• semantic headings/lists for state content
• error screen uses role="alert"
• illustration is decorative only and hidden from assistive tech

Screenshots

Trade-offs

• current dashboard data is still static, so these states establish the design system and copy pattern first
• the home page was left mostly intact to keep this PR focused and easy to review