Feature request: suppress "No stderr output" feedback for sync command hooks with empty stderr

Problem

When a synchronous command hook completes with empty stderr, the CLI always prints:

Stop hook feedback:
[node /path/to/hook.js]: No stderr output

This message provides zero value — it's noise. There is no way to suppress it via settings.json: rewakeSummary only works for asyncRewake: true hooks, and there is no command-quiet type. The only workaround is to have the hook script write a synthetic message to stderr just to avoid the default text.

Proposal

Add a hook-level option (e.g., "showCompletionSummary": false) that suppresses this completion feedback line when stderr is empty. Sync command hooks that produce meaningful stderr output should still show it.

Use case

A Stop hook that runs checks and returns all meaningful output via additionalContext — the stderr channel is unused, so the CLI summarizing empty stderr is just clutter at the end of every session.