How can I access the kali linux desktop menu I get when running kali as a standalone OS, within a kali appvm?
A (template based) Kali appvm does not have a desktop per se, so you
cant access the desktop menu, unless you can find a command which will
make it appear, and map that to a desktop or keyboard shortcut in dom0.
You could try copying the menu from a standalone system and create a
copy in dom0, editing the links to call "qvm-run <kali_appvm> ..", which
would give you a desktop menu in dom0.
If you wanted to be very fancy you could edit the dom0 desktop menu to
include the kali appvm menu.