Enables using Zeta edit predictions with a custom `ZED_PREDICT_EDITS_URL` without requiring authentication to Zed servers. This is useful for: - Development and testing workflows - Self-hosted Zeta instances - Custom AI model endpoints Prior context on this usage of `ZED_PREDICT_EDITS_URL`: https://github.com/zed-industries/zed/pull/30418 Release Notes: - Improved self-hosted zeta UX. Users no longer have to log into Zed to use custom or self-hosted zeta backends. --------- Co-authored-by: Agus Zubiaga <agus@zed.dev>