After a successful switch deployment, the listener now waits for Prometheus
to scrape the /metrics endpoint before exiting for restart. This ensures
deployment metrics are captured before the process restarts and resets
in-memory counters. Falls back to a 60 second timeout if no scrape occurs.
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
Add an optional Prometheus metrics HTTP endpoint to the listener for
monitoring deployment operations. Includes four metrics:
- homelab_deploy_deployments_total (counter with status/action/error_code)
- homelab_deploy_deployment_duration_seconds (histogram with action/success)
- homelab_deploy_deployment_in_progress (gauge)
- homelab_deploy_info (gauge with hostname/tier/role/version)
New CLI flags: --metrics-enabled, --metrics-addr (default :9972)
New NixOS options: metrics.enable, metrics.address, metrics.openFirewall
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
