Base line support for declarative model support, creating Presence States workspaces, and interacting with them.
`PresenceEvents` events are not connected.
Pending update: Update `ISessionClient` to use a stable id for lifetime
and coordinate using system:presence `priorClientIds` (also to be renamed).
Tested manually with modifications to
examples/service-clients/azure-client/external-controller not shown
here.
Jason Hartman