a slight change in packaging (or a major one)... most cases, the replacement package is a refactoring of existing packages. Unfortuneately this does cause some problem during the transitional stages.
Me? What do I do about it?
dpkg -i --force-overwrite /var/cache/apt/archives/manpages-dev_2.24-1_all.deb
From then on the changed package typically has no problems.
Change like these typically happen when a new (to the package) programmer has done the refactoring, mainly due to unfamiliarity of the previous coding styles and practices taken by the previous maintainer.
Why are you installing manpages-dev anyway?
You hate doing documentation!