Pause playback on app quit

[pedromarquetti]

Is your feature already implemented in the latest master?
No, it is a minor feature request

Is your feature request related to a problem? Please describe.
When closing the TUI (q), playback should be paused. If a song is playing and i close the app, then reopen it, the song does not resume where it left off.

Describe the solution you'd like
when quitting the app, maybe it should send a pause command

Describe alternatives you've considered
tried doing

 match command {
        Command::Quit => {
            client_pub.send(ClientRequest::Player(PlayerRequest::Pause))?;
            ui.is_running = false;
        }

but didn't work, i don't know if there's a more correct way of doing it tho.