Port NamBan to LibAdwaita

[behdanisohrab]

For making namban UI more interactive inside Gnome and making it Responsive for mobile devices i recommend to port namban ui to adwaita.

[probonopd]

Please don't. libadwaita doesn't work well outside of the Gnome desktop. Switching to libadwaita would significantly reduce the potential user base for this application, essentially limiting it to the fraction of users who happen to use Gnome.