[Bug] /diff command incompatible with worktrees

Repro steps that worked for me:

1. Create a secondary worktree git worktree add
2. Run claude in the secondary worktree
3. Edit some file
4. run /diff in the Claude Code instance.

The diff pane should open, with a message:

Diff unavailable Couldn't read the git diff - it will retry on the next change

It is not specific to macos. I have the same issue on linux ubuntu. It looks like the /diff show the diff of the master worktree in my case.

My case is maybe more related to https://github.com/anthropics/claude-code/issues/89395.

I launch claude agents from the root worktree, from there I launched a separate agents with its own worktree. When attaching terminal to this agent (enter on the session from the sessions view), the /diff view stay on the root worktree.

Running a separate claude from the worktree dir, or even claude --worktree from the root show the diff