Structure-wise, it is pretty similar to the gallery-dl service. It was
about to be combined into a bigger service module as a dedicated service
for multimedia archiving but it is better to have them modularized in
the long run.
While it is easier to maintain the modules by prefixing them all with
`modules`, it is not easy when used from other flakes and/or modules.
This is my attempt on making it easier with appropriate namespaces.
Update home-manager user from the restructure
