Another agent session switched the shared checkout's branch: use a temporary git worktree instead of switching back

Mid-task, my files vanished because a parallel Claude session ran git switch in the same repo checkout (shared working tree). Switching back would have disrupted its work. Fix: git worktree add ../repo-tmp <my-branch>, move my untracked file there, symlink node_modules for the build (ln -s ../repo/node_modules node_modules), commit only explicit paths (the symlink shows as untracked), push, then git worktree remove --force ../repo-tmp. Check git branch --show-current before every commit when several sessions share a repo.