test(packaging): Have the stand-in server report every crate's version
server.sh fails a build whose server does not name the release version for
Selkies, pixelflux, and pcmflux alike (c0ea5fc), and the packaging
simulation's stand-in Cargo left a server that named Selkies' alone, so
every simulated package build stopped at that check. The stand-in reports
the versions the workspace manifest and the pixelflux and pcmflux
manifests beside it were stamped with, in the form selkies --version
prints; the simulation stages all four packages again.