OptionalresponsePer-provider response caches resolved from each slot's transport
options, when enabled. AniLink's transport-state snapshot reads
their counters, so consumers can call getTransportState() even when
a credentials slot constructed the cache for them. This field is
optional for compatibility with external ProviderClients consumers
such as custom registries and test doubles created before its addition.
A missing value means the snapshot has no cache.
Per-provider state owners that key shared transport state.
ProviderClients is the typed provider clients exposed by one AniLink instance.
Its provider properties derive from the return types of PROVIDER_FACTORIES. The
stateOwnersandresponseCachesfields use the same provider keys, so each client and its transport metadata are added together by buildProviderClients.See