It was supposed to create the directory if it wasn't found which is
self-defeating. In any case, it will still fail if the directory is in
the way of an unmounted device.
There is the `--paths` option for that purpose. It also eliminates the
workaround for creating the directory before starting the service for
newly-bootstrapped systems.
The several hardening options have also been corrected.
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
