Add BLU to Magian Staffs

Counter to "design": MNK had access to most staffs, but not these ones.

Counter to needing skill: RDM and PLD (RDM on the staff, but no skill; PLD off the staff, but has high skill)

I don't think there is a model difference within the staff category as there is with swords.

I all but given up on trying to figure out SE's way of thinking tbh. It seems logic isn't one of the main ingredients in a lot of cases.