Submission confirmation email sent within 5 minutes with a status link

When a submitter clicks submit and gets no email back, they assume the form dropped the request and either re-submit (creating duplicate moderation work) or abandon the directory entirely. Confirmation emails with a tracked submission ID and status link reduce duplicate submissions, cut support volume on "did you get my listing?" tickets, and give the business a legitimate re-engagement channel when the listing is approved. Absent confirmation also breaks CAN-SPAM and GDPR Article 13 transparency expectations around acknowledging data collection at the point of intake.

In app/api/listings/submit/route.ts, generate a stable submission_id inside the same transaction that inserts the listing, then enqueue the confirmation email so the response is not blocked by SMTP latency. The email body must include the ID and a status URL the submitter can revisit:

await sendEmail({
  to: data.contactEmail,
  subject: 'Your listing submission has been received',
  html: `Submission ID: ${submissionId}<br><a href="https://yourdomain.com/submissions/${submissionId}/status">Check Status</a>`
})

Queue the send via a background job so the API returns within 500ms.