Next.js migration: skeleton + static pages

[MaxGhenis]

Part of #811

Goal

Set up Next.js App Router alongside the existing Vite app and migrate the static website pages.

Tasks

• Initialize Next.js 15 in the repo (e.g. next/ folder or top-level restructure)
• Configure Tailwind CSS 4, path aliases, TypeScript
• Set up shared component imports from existing app/src/components/
• Deploy to a Vercel preview URL
• Migrate static pages to file-based routes:
  • /:countryId (home)
  • /:countryId/team
  • /:countryId/donate
  • /:countryId/supporters
  • /:countryId/privacy
  • /:countryId/terms-of-service
  • /:countryId/brand (and sub-routes)
  • /:countryId/claude-plugin
• Set up RedirectToCountry logic (root → /us)
• Port StaticLayout (header/footer) to Next.js layout
• Verify pages render correctly against current production

Notes

• Keep Vite app running in parallel — this is additive, not a replacement yet
• The [countryId] dynamic segment maps naturally to Next.js dynamic routes
• Redux store (metadata) and React Query provider need to be set up as client-side providers

[github-actions]

🎉 This issue has been resolved in version 0.4.0 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

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[policyengine]

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