cleanup: Remove duplicate cookie-banner route, redirect to /sdk/cookie-banner

- Deleted 6 unused components from /sdk/einwilligungen/cookie-banner/_components/
- Replaced page.tsx with Next.js redirect() to /sdk/cookie-banner
- Updated EinwilligungenNavTabs link to /sdk/cookie-banner
- Updated catalog page link to /sdk/cookie-banner
- Single source of truth: /sdk/cookie-banner (Step in "Rechtliche Texte")

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

admin-compliance/app/sdk/einwilligungen/_components/EinwilligungenNavTabs.tsx

@@ -35,7 +35,7 @@ const EINWILLIGUNGEN_TABS = [
   {
     id: 'cookie-banner',
     label: 'Cookie-Banner',
-    href: '/sdk/einwilligungen/cookie-banner',
+    href: '/sdk/cookie-banner',
     icon: Cookie,
     description: 'Cookie-Consent konfigurieren',
   },