The shadow package contains patches to add the scripts useradd.local,
userdel-pre.local, userdel-post.local

They contain a note "Here you can add your own stuff" but clearly they are in
/usr, therefore to be considered readonly and not config files. So that can't
work.

Can we just drop them without replacement please? :-) If there's anything
useful in there it should be implemented directly in C. For example there is a
pr related to SELinux upstream: https://github.com/shadow-maint/shadow/pull/422