agent: Cancel subagents (#47647)

Allows cancelling subagents

Release Notes:

- N/A *or* Added/Fixed/Improved ...

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Co-authored-by: Zed Zippy <234243425+zed-zippy[bot]@users.noreply.github.com>
86772d52e9Cameron Mcloughlin committed on 1/26/2026, 2:00:42 PM· committed by GitHubparent3a94910
4 files changedLine totals unavailable