When a realm has enabled 'use-flatpak' a .desktop file for GNOME
Software will be automatically generated while that realm is running.
This .desktop file will launch GNOME Software from Citadel inside a
bubblewrap sandbox. The sandbox has been prepared so that GNOME
Software will install flatpak applications into a directory that belongs
to the realm associated with the .desktop file.
When a realm has enabled 'use-flatpak' this directory will be bind
mounted (read-only) into the root filesystem of the realm so that
applications installed by GNOME Software are visible and can be launched.
citadel-tool now installed with a hardlink for each binary tool and
dispatches on the exe path to the tool implementation. This makes
the build faster, uses less disk space, and makes it easier to
create new small tools.