Add new editing eval scenario and improve it substantially (#29997)

This improves the new eval scenario by ~80% (`0.29` vs `0.525`) without
decreasing performance in the other evals.

Release Notes:

- Improved the performance of the `edit_file` tool.
07e6e49583Antonio Scandurra committed on 5/6/2025, 12:22:42 PM· committed by GitHubparent6e9f8f9
4 files changedLine totals unavailable