fix email sender all flow

prisma/migrations/20260520000000_add_email_sent_html/migration.sql

@@ -0,0 +1,3 @@
+-- AlterTable: simpan body HTML email terkirim supaya admin bisa resend
+-- (PR-E5) dan investigasi isi email. Nullable — row lama tidak punya body.
+ALTER TABLE "EmailSent" ADD COLUMN "html" TEXT;