Performance, SEO, a11y, and code quality improvements

1. Performance: 25 pages switched from force-dynamic to revalidate=300 (ISR);
   2 pages (community, developers) now fully static (SSG)
2. DB indexes: Added @@index on foreign keys for WebsiteArticles,
   WebsiteArticleReactions, WebsiteArticleComments, WebsiteHelpCenterTickets,
   WebsiteShopArticles, RadioSongRequests, StaffActivities
3. SEO: Added robots.ts, sitemap.ts, canonical URLs, Open Graph + Twitter
   Card metadata on root layout and news articles
4. A11Y: Replaced <details>/<summary> dropdowns with accessible button-based
   NavDropdown (aria-expanded, aria-haspopup, role=menu). MobileNav now
   uses translated aria-label, aria-expanded, aria-controls, role=menu
5. Code quality: Added try/catch to updateArticle/deleteArticle; deleteArticle
   now uses prisma. for atomicity
6. CI/CD: Added GitHub Actions workflow (typecheck + test)
7. i18n: Added openMenu/closeMenu keys to all 6 locales
8. Observability: Health endpoint now checks SMTP reachability when configured
9. Loading states: Added loading.tsx for root, admin, and news sections
10. Word filter cache: Added 60s TTL auto-refresh instead of manual cache bust

prisma/schema.prisma

@@ -1569,6 +1569,7 @@ model WebsiteArticles {
   createdAt DateTime? @map("created_at") @db.Timestamp(0)
   updatedAt DateTime? @map("updated_at") @db.Timestamp(0)
 
+  @@index([userId])
   @@map("website_articles")
 }
 
@@ -1662,6 +1663,8 @@ model WebsiteArticleReactions {
   reaction  String   @db.VarChar(50)
   active    Boolean  @default(true)
 
+  @@index([articleId])
+  @@index([userId])
   @@map("website_article_reactions")
 }
 
@@ -1753,6 +1756,8 @@ model WebsiteArticleComments {
   createdAt DateTime? @map("created_at") @db.Timestamp(0)
   updatedAt DateTime? @map("updated_at") @db.Timestamp(0)
 
+  @@index([articleId])
+  @@index([userId])
   @@map("website_article_comments")
 }
 
@@ -1841,6 +1846,8 @@ model WebsiteHelpCenterTickets {
   createdAt DateTime? @map("created_at") @db.Timestamp(0)
   updatedAt DateTime? @map("updated_at") @db.Timestamp(0)
 
+  @@index([userId])
+  @@index([categoryId])
   @@map("website_help_center_tickets")
 }
 
@@ -1877,6 +1884,7 @@ model WebsiteShopArticles {
   createdAt DateTime? @map("created_at") @db.Timestamp(0)
   updatedAt DateTime? @map("updated_at") @db.Timestamp(0)
 
+  @@index([categoryId])
   @@map("website_shop_articles")
 }
 
@@ -2151,6 +2159,7 @@ model RadioSongRequests {
   createdAt  DateTime? @map("created_at") @db.Timestamp(0)
   updatedAt  DateTime? @map("updated_at") @db.Timestamp(0)
 
+  @@index([userId])
   @@map("radio_song_requests")
 }
 
@@ -2361,9 +2370,11 @@ model StaffActivities {
   description String  @db.Text
   ipAddress  String?  @map("ip_address") @db.VarChar(45)
   metadata   Json?    @db.Json
-  createdAt DateTime  @default(now()) @map("created_at") @db.Timestamp(0)
+  createdAt  DateTime  @default(now()) @map("created_at") @db.Timestamp(0)
   updatedAt DateTime? @map("updated_at") @db.Timestamp(0)
 
+  @@index([userId])
+  @@index([action])
   @@map("staff_activities")
 }