agent2: New thread from summary (#36578)

Release Notes:

- N/A

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Co-authored-by: Agus Zubiaga <agus@zed.dev>
Co-authored-by: Cole Miller <cole@zed.dev>
85865fc950Bennet Bo Fenner committed on 8/20/2025, 1:54:00 PM· committed by GitHubparentc5040bd
6 files changedLine totals unavailable