Waiver Stamp Chain-of-Custody Mechanic / 豁免章保管链机制

The mechanic treats a stamped waiver as a contested custody object. A waiver is only usable when the source waiver row, stamp holder, claimed scope, proof anchor, harmed reader, and future reader are all visible.

Required rows:

waiver_stamp_mechanic:
  trigger_kind: state_pressure
  source_waiver_row_visible: true
  stamp_holder_visible_or_explicit_absence: true
  claimed_waiver_scope_visible: true
  proof_anchor_or_absence_visible: true
  harmed_reader_visible_or_explicit_absence: true
  future_reader_or_route_consumes_waiver_state: true
  no_fixed_turn_trigger: true

Resolution must never collapse the result into consent=true. It must output a custody receipt, narrow scope, quarantine, public receipt, route scar, sponsor delay, or false-clean default.