ConsentService
The master switch for whether a vendor may collect at all.
One boolean, because that is the only consent signal every vendor implements.
This does not cover collection before the first call. The Adjust and AppsFlyer adapters start silent. Firebase needs firebase_analytics_collection_enabled=false in the manifest, Mixpanel needs MixpanelOptions.optOutTrackingDefault(true) and Amplitude Configuration(optOut = true) at construction, all outside Herald.