v0.8.1

• Harden worktree teardown. otta-worktree.sh --remove is invoked by DevOps from inside the worktree being removed. Fixed three issues that left a dangling worktree: a cwd-dependent repo slug (now resolved via the main worktree, stable from any linked checkout), git worktree remove refusing the current directory (now steps out first), and macOS path resolution (/var→/private/var). Regression test now exercises removal from inside the worktree.