[MacOS] switch focus back to the previous window after toggling the quick access (QA) terminal off

[nmder]

Is your feature request related to a problem? Please describe.
In macos, when you toggle the QA terminal off, the focus does not return to the last window. You need to click on the window to regain focus. It is a general macos behavior. However, the QA terminals of both ghostty and iterm2 somehow circumvent this. It would be nice to have this behavior here as well.

Describe the solution you'd like
A focus_policy option to allow returning focus to the last window.

Describe alternatives you've considered
Ghostty and iTerm2 alternatives exhibit this behavior.

Additional context
Add any other context or screenshots about the feature request here.

[kovidgoyal]

Feel free to study their source code and figure out how they did it and
send a PR. If I had to guess they are probably manually storing the
previously active window and then asking the OS to restore focus to it
using some Cocoa API or the other when their window is hidden,
I vaguely remember trying to do that when I was developing the feature but I couldn't get it to work well.