feat: add end-to-end observability (metrics, health, mobile RUM, dashboards, alerts)
- Backend: OTel metrics via OTLP -> Alloy -> Prometheus (OTEL_METRICS_EXPORTER=otlp)
- New business metrics (src/metrics.js): searches, CIMA latency/errors, cache
hits/misses, logins, rate-limits, pharmacy writes/links, push sent/failed,
DB + Redis timings/errors, HTTP req count/duration, heartbeat
- Backend health endpoints /healthz and /readyz
- Mobile (Expo): Grafana Faro RUM via @grafana/faro-react-native
- redis/postgres exporters in docker-compose + Prometheus scrape jobs
- Grafana dashboards (backend, datastores, mobile RUM, overview)
- Prometheus alert rules (farmafinder_*) -> existing Alertmanager (Telegram)
- Design/spec saved to docs/superpowers/specs/
Antoni Nuñez Romeu
839c64c12a