Better notification for multi-agent

What variant of Codex are you using?

codex cli v0.104

What feature would you like to see?

With this implementation https://github.com/openai/codex/issues/11701, we’ve added more agents but the notification system has become noisy.
I used the notify.py script to get notifications.

This needs improvement.
For example, we could have a configurable notification level and only allow notifications from agents at a certain depth.

Also, if https://github.com/openai/codex/issues/12047 is done. Those infomatin can also be exposed to notification. For personal customization, I could have a better cloud notification with more useful info by tweaking that notify.py.

Additional information

_No response_