agent2: Always finalize diffs from the edit tool (#36918)

Previously, we wouldn't finalize the diff if an error occurred during
editing or the tool call was canceled.

Release Notes:

- N/A

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Co-authored-by: Antonio Scandurra <me@as-cii.com>
b249593abeBen Brandt committed on 8/26/2025, 9:46:29 AM· committed by GitHubparentc14d84c
3 files changedLine totals unavailable