Add incoming flagged emails to global suppression list

Flagged emails arrive by webhook and mustn't be messaged, causing bounces and deliverability damage. Add them to suppression to keep lists clean before each campaign.

Overview

Avoid sending campaigns to addresses already flagged by external systems and protect sender reputation. The flow ingests webhook flags and adds those emails to your suppression endpoint within minutes so deliverability managers won't send to blocked addresses before the next campaign.