[FEATURE]: Allow installing package groups

[axtloss]

Is your feature request related to a problem? Please describe.

Currently when trying to install any package group like gnome, amethyst just says that the package couldn't be found, but pacman can install it without any issues.

Describe the solution you'd like

Amethyst should be able to install package groups using pacman

Describe alternatives you've considered

just using pacman, but that can be a bit troublesome since I don't always know when something is a package group

Additional context

No response