argoyle
717ac59faf
SetupOTelSDK now adds service.instance.id (the pod hostname) to OTEL_RESOURCE_ATTRIBUTES. The OTLP->Prometheus exporter maps it to the `instance` label on both metrics and target_info, which (1) stops multi-replica services from colliding on a single series and (2) gives PromQL joins a unique (job, instance) key. Falls back to the service name when the hostname is unavailable.