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>

prisma/schema.prisma

@@ -278,6 +278,10 @@ model User {
   // Award overrides
   awardEligibilityOverrides AwardEligibility[] @relation("AwardEligibilityOverriddenBy")
 
+  // In-app notifications
+  notifications            InAppNotification[] @relation("UserNotifications")
+  notificationSettingsUpdated NotificationEmailSetting[] @relation("NotificationSettingUpdater")
+
   // NextAuth relations
   accounts       Account[]
   sessions       Session[]
@@ -759,6 +763,55 @@ model NotificationLog {
   @@index([createdAt])
 }
 
+// =============================================================================
+// IN-APP NOTIFICATIONS
+// =============================================================================
+
+model InAppNotification {
+  id          String    @id @default(cuid())
+  userId      String
+  type        String    // FILTERING_COMPLETE, NEW_APPLICATION, ASSIGNED_TO_PROJECT, etc.
+  priority    String    @default("normal") // low, normal, high, urgent
+  icon        String?   // lucide icon name
+  title       String
+  message     String    @db.Text
+  linkUrl     String?   // Where to navigate when clicked
+  linkLabel   String?   // CTA text
+  metadata    Json?     @db.JsonB  // Extra context (projectId, roundId, etc.)
+  groupKey    String?   // For batching similar notifications
+
+  isRead      Boolean   @default(false)
+  readAt      DateTime?
+  expiresAt   DateTime? // Auto-dismiss after date
+
+  createdAt   DateTime  @default(now())
+
+  // Relations
+  user        User      @relation("UserNotifications", fields: [userId], references: [id], onDelete: Cascade)
+
+  @@index([userId, isRead])
+  @@index([userId, createdAt])
+  @@index([groupKey])
+}
+
+model NotificationEmailSetting {
+  id                String   @id @default(cuid())
+  notificationType  String   @unique  // e.g., "ADVANCED_TO_ROUND", "ASSIGNED_TO_PROJECT"
+  category          String   // "team", "jury", "mentor", "admin"
+  label             String   // Human-readable label for admin UI
+  description       String?  // Help text
+  sendEmail         Boolean  @default(true)
+  emailSubject      String?  // Custom subject template (optional)
+  emailTemplate     String?  @db.Text  // Custom body template (optional)
+
+  createdAt         DateTime @default(now())
+  updatedAt         DateTime @updatedAt
+  updatedById       String?
+  updatedBy         User?    @relation("NotificationSettingUpdater", fields: [updatedById], references: [id])
+
+  @@index([category])
+}
+
 // =============================================================================
 // LEARNING HUB (Phase 2)
 // =============================================================================