git rebase interactive breaks when working on a secondary worktree

git rebase interactive breaks when working on a secondary worktree

## What did you do before the bug happened?

1. `git clone` a repository.
2. `git worktree add` to have a second branch checked out in another directory.
3. Continue working as normal. The main branch has a bunch of extra
commits (at the main worktree).
4. At the second worktree, after a while, try `git rebase -i
hash_of_a_few_commits_ago`, or `git rebase -i main` (where main is the
main branch at the main worktree).
5. Approve the plan, even without any changes.

## What did you expect to happen?

It should work.

## What happened instead?

I get this error:

    error: Your local changes to the following files would be
overwritten by checkout:

Followed by a list of several files that were NOT changed in my secondary branch at my secondary worktree.

What's more, if I redo the `git rebase` but without `-i`, it works fine without any errors.

## What's different between what you expected and what actually happened?

If I try following the exact same steps (the exact same git rebase -i) on the exact same branch, but this time having it checked out at the main worktree, then everything works.

## Anything else you want to add:

I've been hitting this error for several months.

It doesn't happen every time, it depends on the commits from both branches. Thus, it's hard for me to give you a minimal reproducible example git repository.

Given the circumstances, I believe some part of the `git rebase --interactive` codepath is not working correctly with worktrees, and thus it's misbehaving.

[System Info] git version: git version 2.49.0 cpu: arm64 no commit associated with this build sizeof-long: 8 sizeof-size_t: 8 shell-path: /bin/sh feature: fsmonitor--daemon libcurl: 8.7.1 zlib: 1.2.12 uname: Darwin 24.5.0 Darwin Kernel Version 24.5.0: Tue Apr 22 19:54:29 PDT 2025; root:xnu-11417.121.6~2/RELEASE_ARM64_T6030 arm64 compiler info: clang: 17.0.0 (clang-1700.0.13.3) libc info: no libc information available $SHELL (typically, interactive shell): /bin/zsh

[Enabled Hooks] applypatch-msg commit-msg post-applypatch post-checkout post-commit post-merge post-rewrite pre-applypatch pre-auto-gc pre-commit pre-merge-commit pre-push pre-rebase prepare-commit-msg