feat: nambahin link field di Notification

prisma/migrations/20260706134239_add_link_to_notification/migration.sql

@@ -0,0 +1,2 @@
+-- AlterTable
+ALTER TABLE `notification` ADD COLUMN `link` TEXT NULL;

prisma/schema.prisma

@@ -356,6 +356,7 @@ model Notification {
     id_admin    Int?     // For mentors/admins
     title       String   @db.VarChar(255)
     message     String   @db.Text
+    link        String?  @db.Text
     is_read     Boolean  @default(false)
     created_at  DateTime @default(now())