KIE Tools - Monorepo improvements

After the migration of `kogito-editors-java`, we have a complete Monorepo on Kogito Tooling. Although other repositories will still be migrated to it (`kogito-apps UI packages`), there's already room for improvement on the whole Monorepo strucutre.

This epic gathers the individual tasks that together will make the Monorepo structure more flexible and robust.