We need to enforce having the licensing terms for the article in the article itself. There could be some automatic choices (CC-BY is what we recommend), but also the government no copyright choice, that they can just check off. There will be a few exceptions, but that can just involve a field that can't be empty for now. Something along these lines for CC licenses (https://wiki.creativecommons.org/wiki/Marking_your_work_with_a_CC_license).
On the left below the GitHub notice seems like a good place.