How should exit hooks be added/removed?

[CanadaHonk]

Since we can exit, we should likely add exit hooks as suggested by @lucacasonato. How should they be added/removed? (also todo bikeshed exit hook or exit listener or ...)

Just like this?

const hook = () => console.log('Goodbye!');
CLI.addExitHook(hook);
// CLI.removeExitHook(hook);