- Move /tmdb route to /search (index, movie detail, tv detail)
- Update / route to show upcoming shows/movies from user's list
- Update all navigation and redirects to point to new routes
- Replace fetchWithEvent with plain fetch to fix client-side crash
- Add Search link to nav bar for logged-in users

Replace createResource with createSignal + onMount in AuthRoot to prevent
hydration mismatch. The server was serializing null auth state, causing
infinite redirect loops after login. Now auth is checked client-side only
after hydration.

Also fix login and register pages to use full page navigation
(window.location.href) instead of client-side navigate to ensure
auth state is refreshed on redirect.

- API routes for movies (popular, search, detail) and TV (popular, search, detail, seasons)
- Movie/TV show listing page with search and media type toggle
- Clickable cards linking to detail pages
- TV detail page shows episodes, next upcoming episode, and aired status
- Movie detail page shows poster, backdrop, rating, runtime, genres, overview
- Styles for all new components and pages
- Uses VITE_TMDB_API_KEY env var for TMDB API access