Draft: Include an abstraction for verified apps
And implement it for flathub and snap.
Draft because:
- it could make sense to have a specific icon for it
- it would be interesting to think of other places we might want to use the information
- not super stoked with the tooltip approach
- needs https://github.com/snapcore/snapd-glib/pull/143 for snap
- needs https://github.com/ximion/appstream/pull/591 for flatpak
Edited by Aleix Pol Gonzalez