feat: multiloader publishing

[MichaelHillcox]

I've only tested locally but it appears to work.

Things to note:

• If you don't publish to the same CurseForge project, you will need to adjust the project id
• The maven target current looks like this if you don't want that, edit the artifactBase inside of the multiloader-common.gradle file
• You should be able to yeet mono folder now
• Test all jars from the publishMods task before running the CI
• Your existing .github/workflows should work like normal