[feature request] audible bell when agent is finished

What feature would you like to see?

I'm sometimes letting the agent run while I do something else, like solve a rubik cube, watch youtube, or browser the web. When running long tasks, I have to check often to see if it's done, it would be nice to have a subtle bell that alerts me when it's done, so I can get back to the task promptly.

Additional information

_No response_