why
The lineage behind the proposition with the given id, assembled from its durable fields.
Return
the lineage, or null if no such proposition exists; null by default
open override fun whyExplain(propositionId: String, contextId: <Error class: unknown class>?): PropositionLineage?
Native lineage: read the proposition's own durable fields (provenance, grounding, reinforcement, status, temporal) and resolve its abstraction sources via findSources. A non-null contextId treats a proposition in another context as absent (null), matching the portable facade's scoped lineage. Null when no such proposition exists.