[MoM] Add MIND_SEEING flag, give it to the hidebehind, rework hidebehind so it uses its powers to hide (and thus you can see it if you have Telepathic Shield up)

[MoM] Add MIND_SEEING flag, give it to the hidebehind, rework hidebehind so it uses its powers to hide (and thus you can see it if you have Telepathic Shield up) #75219