Readonly InternalfamiliesPer-provider registry consumed by useCauslFamily. Each
<CauslProvider> mount owns a fresh map so two providers
around the same graph keep their own family namespaces; nodes are
not shared by accident.
Readonly InternalfamilyProvider-instance prefix applied to every engine node id a family
factory registers (#132). The engine has a single id namespace, so
two <CauslProvider> mounts over the same graph would collide
with DuplicateNodeError the moment they register the same
factory-derived id. Prefixing each provider's family ids with a
unique string keeps the isolation the family registry promises at
the React level honest all the way down at the engine level: the
same key resolves to two distinct engine nodes, one per provider.
Generated once per provider mount alongside families and stable across renders (both are keyed on the graph handle). Reset when the host swaps the graph, so the new graph gets a fresh namespace with no leak from the old one.
ReadonlygraphOptional Readonlyupdate
Shape of the value travelling through CauslContext.
Remarks
updateis optional: a provider may supply a graph for read-only subscription consumers without also installing a dispatch surface. Hooks that need dispatch (see useDispatch) throw a descriptive error whenupdateis absent.