Run Hermes from any git worktree without a full per-worktree reinstall.
A git worktree only carries tracked files, so a fresh worktree has no
node_modules (~1.3G) and no .venv. These launchers make a worktree runnable
by sharing the main checkout's deps when they're byte-identical, and falling
back to a local install (stamped, so it only reinstalls when the lockfile
actually changes) when the branch bumps a dependency.