This currently creates a **placeholder** widget that simply displays the setting value. I do have a local copy with proper widgets for most cases, but I need to go through and confirm that everything useful is covered (`GVariant` is very flexible, but I think settings are less so.)
Additionally, because of the way that settings are loaded from the devenv, we don't get the summary/description, so those won't load just yet. I've left those out of here for now so this only displays the key name. Once https://gitlab.gnome.org/GNOME/glib/-/merge_requests/2893 is complete, then we can put everything into a resource and the summary/description will work properly.