Class FactStore

Insert facts. Facts with predicates outside the closed schema are silently dropped (matches the FactExtractor contract). Subjects are canonicalized; the stored form carries the canonical subject. Per-(subject, predicate) entries stay time-sorted ascending so getLatest is O(1) and getAllTimeOrdered is O(n).

Return the latest fact for (subject, predicate) or null. Supports un-canonicalized subject input (canonicalized internally). Returns null for predicates outside the closed schema.

Return ALL facts for a subject (across predicates), time-sorted ascending. Used for temporal queries where history matters.