Post deployment start message to engineering team channel

Merged pull requests trigger deployments without channel context, leaving release engineers unsure of rollout timing. The workflow posts clear start notices so teams can monitor and respond within 20 minutes.

Overview

Merged PRs often start invisible rollouts that leave engineers and product owners without context; this flow posts a clear deployment-start message to your release channel so everyone knows a rollout began. That visibility shortens time-to-detect issues and enables team response within the first 20 minutes of deployment.