sl-justification-is-disjunctive

Summary

A node only needs one good reason to be considered true. If it has multiple justifications, the system checks them one by one and stops as soon as it finds one that works — it doesn't require every justification to be valid simultaneously. This means adding a new justification can only make a node easier to support, never harder, and retracting one justification won't necessarily bring the node down if another still holds.