For Service Mesh 3, we should look to introduce a handful of custom metrics that help to measure. We should implement new custom telemetry data collection investigated in the https://issues.redhat.com/browse/OSSM-11379 and integrate Sail Operator with the Red Hat Telemetry service.
We should extend the operator telemetry metrics we did in Service Mesh 2 and collect additional custom metrics.
Related operator changes in Service Mesh 2:
https://github.com/maistra/istio-operator/pull/1119
https://github.com/openshift/cluster-monitoring-operator/pull/1925

AC:

• Implement pulling of metrics from istiod, envoy proxy and ztunnel instances into the operator (if necessary - telemetry probably only scrapes the operator's endpoint).
• Register the metric counters for export in the Sail Operator.
• Send new custom metrics to the Red Hat Telemetry service.
  https://rhobs-handbook.netlify.app/products/openshiftmonitoring/telemetry.md/