fix focus stealing prevention for --edit mode

[allisonkarlitskaya]

boxi --edit will attempt to raise an existing window in the event that the file is already open. This currently doesn't work, because there's nothing to wire the timestamp from the user pressing the enter key through to boxi to be passed back (via D-Bus) to boxi to be allowed to raise its own window.

It's not clear what a good solution here would look like. This might require patching VTE, implementing some sort of OSC sequence, or some D-Bus service associated when the application window, in order to allow launched programs to get access to the timestamp of the most recent keystroke.

[allisonkarlitskaya]

Long running VTE discussion https://gitlab.gnome.org/GNOME/vte/-/issues/2125