Function take_every_level_alive 

pub fn take_every_level_alive() -> bool

phase-509 P7 (RFC-0108 D8) – which level an executor is, and whether every level of the image is alive: what a supervisor that owns a route per level or feeds a watchdog reads, and what a board’s tier runner states (the level count, and each tier’s level by tier_level_by). Plain atomics in nros-node, so ungated. The watchdog feed: true when every level has checked in since the last true, and the check-ins are then cleared; false, and nothing cleared, while any level has not.