KIP-835 — Monitor KRaft Controller Quorum Health

Accepted Kafka 3.3 MetricsKRaft

Introduces a `NoOpRecord` written periodically to the `__cluster_metadata` log to advance the high-watermark, and exposes KRaft controller quorum health metrics so monitoring systems can verify that committed offsets are progressing. Without this, a quorum that has stalled (e.g. due to a missing majority) cannot be detected by watching offset advancement alone.

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