tick
def tick(mut self: Scheduler, now: Int64)One pass: reap ended runs, advance rebuilds, make due fires, sense new snapshots, schedule retries, and start what may start.
orca.tickOne pass of the scheduler (orca tick; orca scheduler makes one a second): what each registered pipeline is due, started.
tickdef tick(mut self: Scheduler, now: Int64)One pass: reap ended runs, advance rebuilds, make due fires, sense new snapshots, schedule retries, and start what may start.