KIP-564 — Add new cached authorizer:change the dim of cache

Accepted Security

Introduces a result-level authorization cache in the broker's ACL authorizer, keyed on `(principal, operation, resource)` tuples, so repeated authorization checks for the same subject skip ACL list traversal and return a cached decision. Without caching, each request triggers a full ACL scan over all entries which becomes a CPU bottleneck on clusters with tens of thousands of ACLs.

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