Fix Mattermost GitHub Webhook

## Problem GitHub webhook to `https://comms.optimified.com/plugins/github/webhook` returns 401 (Unauthorized). The webhook secret configured in GitHub doesn't match the one in Mattermost's GitHub plugin settings. ## Steps 1. Go to **Mattermost System Console → Plugins → GitHub → Webhook Secret** — copy the value 2. Go to **GitHub repo → Settings → Webhooks → edit webhook** 3. Paste the correct secret and save 4. Click **Redeliver** on the last failed delivery to verify