feat: harden admin security, add AI trip planner, map view, and SEO/notification improvements

Security:
- requireAdmin() session check added to every admin-only server action
  (previously relied only on middleware path matching, which Next.js
  Server Actions don't reliably respect)
- Real Prisma + bcrypt admin auth, replacing hardcoded credentials; split
  into an Edge-safe auth.config.ts (used by proxy.ts) and the full
  Prisma-backed auth.ts (route handler, server actions, server components)
- Removed hardcoded fallback secret on the Instagram sync cron endpoint
- Honeypot field + per-IP rate limiting on contact/business-submission
  forms and the analytics events endpoint

Features:
- AI trip planner (/plan-olustur, /plan/[id]) backed by DeepSeek, grounded
  to only recommend isLocalApproved listings, with a deterministic
  link-injection fallback for anything the model doesn't format as markdown
- Interactive Leaflet/OpenStreetMap view on category listing pages
- Telegram notifications for new contact messages and business submissions

SEO:
- Brand-consistent favicon/apple-icon/PWA icons and default Open Graph/
  Twitter share images, generated via next/og (replacing default Next.js
  placeholders)
- BreadcrumbList structured data on category and listing detail pages
- Fixed two remaining raw <img> tags to use next/image

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

messages/ru.json

@@ -33,6 +33,7 @@
     "generate": "Создать план поездки",
     "generating": "Подготовка вашего плана...",
     "viewPlan": "Посмотреть план",
+    "placesInPlan": "места из этого плана",
     "styles": {
       "gastronomy": "Гурман и гастрономия",
       "relaxation": "Покой и отдых",
@@ -70,7 +71,8 @@
     "address": "Адрес",
     "phone": "Телефон",
     "price": "Цена",
-    "viewDetails": "Подробнее"
+    "viewDetails": "Подробнее",
+    "map": "Вид на карте"
   },
   "detail": {
     "approved": "Заведение со знаком «Одобрено местными»",