- Remove GRAFANA_URL from backend environment (backend never consumed it).
- Add VITE_GRAFANA_URL to frontend build-args (prod), dev environment, and
frontend/Dockerfile ARG/ENV so Grafana deep-links resolve correctly.
- Add ALERTMANAGER_WEBHOOK_URL to backend environment so the documented
alert-forwarding feature is reachable from compose.
- Document VITE_GRAFANA_URL in .env.example.
Developer
alex