Ensure Y Transparency bundle deltas don't slip and slide the opaque left or right

The Y Transparency bundle needs the same qa-proofing script as GRAD to ensure no advance width shifts occur, but also additional qa-proofing to ensure the glyphs don't shift around within the advance width; possibly ensuring side bearing values don't change, but possibly they might in a valid way, so in that case it might need code similar to parama-roundup to ensure certain left/right most points don't move in the x dimension.

I found this as the `Z` kept shifting around: