agent: Show error message of edit tool call in UI (#57722)

Ensures that we show the error message of the `edit_file`/`write_file`
tools in the UI

Release Notes:

- agent: Fixed an issue where errors would not show up in the UI if an
edit tool call failed
a60cf568b7Bennet Bo Fenner committed on 5/26/2026, 2:10:06 PM· committed by GitHubparent16ae765
3 files changedLine totals unavailable