Add notification bell system and MOPC onboarding form

Notification System:
- Add InAppNotification and NotificationEmailSetting database models
- Create notification service with 60+ notification types for all user roles
- Add notification router with CRUD endpoints
- Build NotificationBell UI component with dropdown and unread count
- Integrate bell into admin, jury, mentor, and observer navs
- Add notification email settings admin UI in Settings > Notifications
- Add notification triggers to filtering router (complete/failed)
- Add sendNotificationEmail function to email library
- Add formatRelativeTime utility function

MOPC Onboarding Form:
- Create /apply landing page with auto-redirect for single form
- Create seed script for MOPC 2026 application form (6 steps)
- Create seed script for default notification email settings

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/server/routers/_app.ts

@@ -30,6 +30,7 @@ import { applicationRouter } from './application'
 import { mentorRouter } from './mentor'
 import { filteringRouter } from './filtering'
 import { specialAwardRouter } from './specialAward'
+import { notificationRouter } from './notification'
 
 /**
  * Root tRPC router that combines all domain routers
@@ -66,6 +67,7 @@ export const appRouter = router({
   mentor: mentorRouter,
   filtering: filteringRouter,
   specialAward: specialAwardRouter,
+  notification: notificationRouter,
 })
 
 export type AppRouter = typeof appRouter