OptionalknownThe name to learn. Omit (or pass null) for a bare sighting that
only advances lastSeen — a non-null value is never downgraded
to null by know (use BeliefStore.forgetField for that).
OptionalregardRegard realm: the viewer's signed attitude toward the referent
(-100..+100; absent or 0 = no opinion). A value, not a flag —
a planned divergence under the payload rule, exactly as knownAs is a
value on the spine. Unlike knownAs's raise-only coalesce, know
overwrites this on set: the delta arithmetic + range clamp live in
the consumer (RegardApi/RegardLogic), never in the store.
OptionaltypeIdentification realm: the viewer knows what kind of thing the referent is. Binary in v1 (unidentified ↔ identified); partial levels defer. Read the actual type name live; this is just the gate.
The bag passed to BeliefStore.know: a partial record update. Carries the spine-level
knownAsalongside any payload flags so a single upsert can raise a name and/or set a flag.