make a new implementation of a version discoverer that completely ignores the maven metadata files that (theoretically) are a programmatically valid list of versions, because it turns out *maven completely ignores the maven metadata files*, maven central performs zero checks that they match reality, and in fact many projects published on maven central contain metadata files that are just flat wrong.

i've known for a while now that there's no programmatic API to list files in a release on maven, and that wound is half-healed if still sore... but now i'm finding that there's no way to programmatically list versions either?  unfuckingbelievable.  this is literally inferior to an unauthenticated ftp server.
notes on the attempt to use a programmatic maven parser Sonatype wrote (or started writing, but gave up); it also doesn't work, due the fact it has faith that literally anything about maven central isn't broken and wrong.
tone down some of the repack logic.  for maintaining anything about packs, mdm-mirror is more appropriate; by default mdm-import-mvn will now do entirely nothing.
hack to carry on in the face of maven releases that didn't actually release anything.