Add the ability to make caelestia menus via command

[AleksElixir]

add the ability to add commands with complexity like the calc and variant command. This feature would help me, put most of the grub menus and features I use into my caelestia workspace. For example I have a grub menu where I can choose what hyprland config to modify, and putting all those commands into the alr crowded commands menu would make it too crowded.