Feature: Use OSC 9 / OSC 777 Terminal Notifications when input is required, or long running jobs are completed

This idea comes from several months of using Claude Code - I really miss the simple feature it uses, when using modern terminals, to alert that user that it needs attention (because it is asking the user a question or for confirmation) or that it has completed some long running work.

Modern terminals (kitty, urxvt, foot, iterm2, wezterm, ghostty, blink shell, and more) support OSC sequences 9 and/or 777: 9 is simpler, 777 has more fields that can be shown. The terminal application then hooks into the system-wide notification system, and intelligently pops a notification for the user see, even if the terminal is in the background, or the user is on a different virtual desktop etc. Clicking on the notification will take you to the terminal application, and, in the ones I use, to the window and tab that requires attention.

See https://docs.blink.sh/basics/notifications, https://codeberg.org/dnkl/foot/issues/224, https://phyks.me/2014/02/local-notifications-for-weechat-and-urxvt.html and many more

I think QCLI uses a bell notification, but this can easily be missed (if the person is away from their desk, or they have the volume turned down, or sent to unworn headphones etc). A floating notification will be seen either immediately, or whenever the user comes back to the computer.

The simplest flow in QCLI would be to hook it into the existing bell notification for requesting input, and also include a simple OSC 9 notification at the same time.

Deeper integration would involve a Claude Code style hooks system that could notify on any hook (interactive input required, work complete, sub or background task complete, etc)