Broker/Partition counts missing in KRaft mode without controller metrics

Broker Count and Partition Count metrics are missing from Control Center when running in KRaft mode because KRaft controllers are not configured to export metrics to Prometheus.

Configure KRaft controllers to export metrics to Prometheus with required configurations from multi-node manual installation docs. Verify controllers can resolve Control Center endpoint: 'curl -X POST http(s)://c3-host:9021/api/v1/otlp/v1/metrics'. Check Prometheus logs for errors.