[WIP]: Add OpenTelemetry metrics support for ClusterInfo

[aadityaraj7769]

Summary

This PR adds OpenTelemetry (OTel) metrics instrumentation to the ClusterInfoSensor.

Changes

• New Interface: Added ClusterInfoOtelMetricsProvider interface for collecting ClusterInfo metrics via OpenTelemetry

  • CanaryDistributionPolicy

• No-op Implementation: Added NoOpClusterInfoOtelMetricsProvider as default implementation when metrics are disabled

• Integration:

  • Integrated metrics provider into JmxManager constructor which is called from container MP.
  • Metrics provider passed to ClusterInfoJmx for metrics collection.

• Metrics Tracked:

  • Gauges: CanaryDistributionPolicy

Testing

• Updated test fixtures to mock the new metrics provider

Backward Compatibility

• Fully backward compatible - defaults to no-op provider when not configured

[yashness]

This seems wrong. Why would a getter function try to record metrics? getter can't have a side effect of "doing" something.

Also, I'm wondering, why rest.li needs to be aware of otel vs rrd? all rest.li layer should do is "expose" metrics to be recorded & helper methods to read those. container code should use those methods & accordingly record in otel or not based on config flag.