Add eBook purchase flag to contact record immediately

Purchase webhooks arrive without tagging contacts, so segments and sales lack product context. Update contacts with the purchased eBook property so campaign managers can act the same day.

Overview

When purchase webhooks don't write back to contact records, campaign segments and sales follow-up lack product context and momentum. This flow writes a purchased-product property to contacts so campaign managers and sales reps can segment and act on receipts the same day.