feat: add qrCode field to Account for QR re-auth

apps/api/prisma/migrations/20260529052802_add_account_qr_code/migration.sql

@@ -0,0 +1,2 @@
+-- AlterTable
+ALTER TABLE "Account" ADD COLUMN     "qrCode" TEXT;

apps/api/prisma/schema.prisma

@@ -108,6 +108,7 @@ model Account {
   sessionPath String
   displayName String?
   status      AccountStatus @default(ACTIVE)
+  qrCode      String?
   groups      Group[]
   createdAt   DateTime      @default(now())
   updatedAt   DateTime      @updatedAt