feat: add SEO improvements — robots.txt, sitemap, Open Graph, JSON-LD schema
- Add app/robots.ts: block admin/kunden/auth/api, reference sitemap
- Add app/sitemap.ts: list public pages (/, /pakete)
- layout.tsx: add metadataBase, Open Graph, Twitter Card, LocalBusiness JSON-LD, improve title/description with location (Crailsheim, Region Schwäbisch Hall)
- pakete/page.tsx: add Open Graph and canonical URL
- datenschutz/page.tsx: fix title/description encoding (Umlaute)
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
MBO-Tech-IT
9cf15d7deb