Git extension keeps refs/remotes/<upstream>/<branch> permanently open, preventing atomic Git ref replacement on non-Unix filesystems

Does this issue occur when all extensions are disabled?: No

- VS Code Version: 1.130.0
- OS Version: macOS Tahoe 26.5.2

Steps to Reproduce:

1. Open any project with `.git` (and a connected remote with e.g. `refs/remotes/origin/master`) on a non-Unix file system where open files can't be unlinked (e.g. a SSHFS-mounted directory with a a non-Unix OS on the other side).
2. Try to push/pull/fetch, run `git pack-refs` or any other command that changes/updates remote refs.

Git will complain that it can't rename (or unlink) `refs/remotes/origin/master` because the file is held permanently open by VS Code's file watcher.

The responsible part of the code is these lines:

https://github.com/microsoft/vscode/blob/05c208e9e28d8c1c723fa08f85e2b7a96092e8e5/extensions/git/src/repository.ts#L490-L492

I did some testing by patching `repository.ts` locally to simply return from `updateTransientWatchers` early before installing a watcher and it expectedly fixes the problem (and the rest of Git extension's functionality, except immediate notifications about upstream changes, seems to remain intact).

A better solution would be to watch the `refs/remotes/` directory instead of watching (effectively keeping open) individual ref files. These files are atomic mutable objects in git and keeping them open indefinitely does not look correct.