KIP-1372 — Reject topic configurations where min.insync.replicas exceeds the replication factor

Discussion AdminBroker

Adds validation to CreateTopics and (Incremental)AlterConfigs that rejects with INVALID_CONFIG any topic whose min.insync.replicas exceeds its replication factor, instead of accepting the value and silently clamping it. Since KIP-966 defines the effective minimum ISR as min(min.insync.replicas, replication factor), such configurations are silently ignored today, leaving operators believing they have a durability guarantee that does not exist and producers with acks=all hitting unretriable-in-practice NotEnoughReplicasException loops that flood broker logs.

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