Prometheus metrics + health endpoints

[gaurangkudale]

Overview

Implement Prometheus metrics and Kubernetes health endpoints for observability.

Metrics to Implement

• rca_incidents_detected_total — counter
• rca_incidents_resolved_total — counter
• rca_watcher_events_processed_total — counter (per watcher type)

Health Endpoints

• /healthz — liveness probe
• /readyz — readiness probe

Tasks

• Register Prometheus metrics in cmd/main.go
• Instrument correlator and watcher code with metric increments
• Expose /healthz and /readyz HTTP endpoints
• Add structured JSON logging using zap with incident ID correlation field
• Update Helm chart to configure liveness/readiness probes

Phase

Week 6 — Part of v0.1 Foundation observability.