Staircase 0.1.6 — multi-device: a ratchet repair only for a collision on our own leaf (another member's duplicate generations no longer make every device commit), inbox: invites sealed to another device's key package stay out, an already-used invite can't roll a group back, Dismiss on invites; Quartz re-vendored at aefbcd0b2a (upstreamed patches 1, 2, 3, 9, 10, 11, 12)