Overview
The %doc change shall be reverted as well.
So the docs should be provided with the library package? I doubt any user would read those, would it not make sense to provide those with the devel package for users developing with it?
But I am fine with reverting this if whished
with your change, installing the devel package becomes mandatory to read the docs, which is not what I'd want.
At least the NEWS file may be interesting to users as well (although the same information should actually be available in the package changelog too). README.md is probably not very useful at all considering its content..
Anyway, I see no reason to move them to the devel package either.
The main idea was: Usually the lib package got installed automatically (because some other package depends on it). Then I would guess 99% of the used either do not even know the package is installed or does not care about changes to dependencies. So for the majority this only adds unneeded files to the system.
But if you are developing with it, you might want to know whats changed.