chore: convert fan screw holes to inserts chore: remove stepped fan cutout for printability

chore: add deskpi rackmate ups and battery mounts

chore: update step file

chore: countersink fan mount holes

chore: re-size back screw holes for m3 inserts

chore: re-arrange port labels

chore: make case shell easier to print

chore: add inset labels to faceplate

chore: move battery brace mounting holes to clear battery terminals

chore: add half-rack step file