Migrate from Pages Router to App Router

[tmshv]

Summary

• Migrated the entire frontend from Next.js Pages Router to App Router
• Introduced route groups: (default) for regular pages, (map) for the map page — replacing the router.pathname == '/map' check in _app.tsx
• Split the monolithic _app.tsx into separate files: root layout, client providers, and per-route-group layouts
• Split the monolithic IndexPage component into 5 focused components: HeroSection, TimelineSection, MapCTA, SurveyCTA, Sponsors
• Converted pages/api/indexFeedback to App Router route handler
• Replaced next-seo with native metadata export
• Removed getServerSideProps from map page (was providing empty fallback data)
• Extracted font definition to fonts.ts to keep root layout server-renderable
• Added missing 'use client' directives to components that use hooks
• Wrapped useSearchParams() usages in Suspense boundaries

🤖 Generated with Claude Code

[manhir]

fixed some styles, looks alright ¯_(ツ)_/¯