Class DelegationNarrator

Cancels any deferred spoken update, drops the digest buffer and resets the burst-timing state.

Consumes one delegated-run progress event: significant steps only; always a context note; and a throttled spoken update when the provider can voice one.

Runs one delegated call through delegate while owning the narration burst around it: progress events are threaded back through DelegateToTargetRequest.OnProgress, and when the delegation finishes (success, failure or abort) any still-pending spoken update is cancelled — the final result is about to be voiced.

Owns the narration burst around any delegated work: anchors a burst when work starts and cancels pending narration when it settles. Use this directly when the caller threads HandleProgress through as the delegated run's own progress callback (the bridged-call path), rather than through Run.