Add old_text/new_text as a zeta2 prompt format (#42171)

Release Notes:

- N/A

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Co-authored-by: Agus Zubiaga <agus@zed.dev>
Co-authored-by: Oleksiy Syvokon <oleksiy.syvokon@gmail.com>
Co-authored-by: Ben Kunkle <ben@zed.dev>
Co-authored-by: Michael Sloan <mgsloan@gmail.com>
b607077c08Max Brunsfeld committed on 11/10/2025, 10:44:54 PM· committed by GitHubparente5fce42
7 files changedLine totals unavailable