Move settings into Commerce > Configuration > Products > Availability settings and add to .info.yml

Dedicated permission is also missing! Seems this was stricked and reviewed with a heiße Nadel :D

We also don't need an extra parent item, no idea what this should have been useful for.

I started implementing the fixes, but please has to be finished @grevil. Thanks :)

Changes LGTM and work as expected! I added the permissions.yml, please do a final review.

Great, fixed! :)

Automatically closed - issue fixed for 2 weeks with no activity.