Implement multi-window multi-burn-rate SLO alerting using Prometheus recording rules and Sloth

Steps

1. Define an SLO spec in Sloth YAML format with slo.service, slo.slos[].name, slo.slos[].objective (e.g., 99.9), and slo.slos[].sli.events specifying error and total metric selectors
2. Run sloth generate -i slo-spec.yaml -o slo-rules.yaml to output Prometheus recording rules and multi-window multi-burn-rate alerting rules conforming to the Google SRE Workbook alert method
3. Apply the generated rules to Prometheus via your Kubernetes PrometheusRule CRD or by adding to prometheus.rules config; rules create metrics like slo:sli_error:ratio_rate5m and slo:burnrate5m
4. The generated alerts come in page and ticket severity pairs: a page alert fires when the short window AND long window both exceed the burn-rate threshold (e.g., 14.4x budget consumed in 1h/5m); ticket alert fires at lower thresholds (e.g., 6x in 6h/30m)
5. Wire the page-severity alert to your PagerDuty or Opsgenie integration via Alertmanager routes using the severity label set by Sloth
6. Validate burn rate calculations: at a 14.4x burn rate for a 99.9% SLO, the error budget would exhaust in approximately 1 hour — use this as a sanity check for threshold tuning