Make it easier to know the session I'm currently using

What problem would this solve? I use different ACP clients. I want to resume a session in a different one, or maybe in the terminal. It is hard to know the session I'm at.

What would a good outcome look like? I have a way to find the current session I'm using, from within the session.

Possible approaches /status should report it.

Additional context

• I have verified this does not duplicate an existing feature request

Do not begin implementation until the issue reaches Ready on the Goose Issues board.