Submission polish: submitting an id that already exists in the catalog is now refused INSTANTLY on the Amiga with a clear explanation (new versions are picked up by the nightly refresh automatically - no submission needed); both GUI forms and the CLI gained a category picker (CAT= keyword in the Shell), so entries arrive pre-sorted for review. Courier-side, every submission's SHA-256 is now re-verified against a fresh download before a review branch opens - a corrupted download on the submitting machine can no longer produce a broken catalog pin.