Retromod

Hotfix for the JPMS module conflict that prevented beta.2 from loading on Forge 1.20.x. Forge's module resolver was refusing to load Retromod because two modules (retromod and com.google.gson) both exported the same Gson packages to the minecraft module.

Fix: every bundled dependency is now relocated under com.retromod.shaded.* so there's nothing to collide with Forge's own bundled libraries.

Behavior is unchanged from beta.2 otherwise. Fabric, Quilt, and NeoForge users were not affected by this bug and don't need to update (beta.2 is fine for them).