Start the avatar session.
Subclasses should override this method and call super.start(agentSession, room) at the
top of their implementation. Subclasses may widen the return type (e.g. returning a
session id), matching the # type: ignore[override] escape hatch used in Python.
Base class for avatar plugin sessions.
Plugin implementations should extend this class and call
super.start(agentSession, room)first in their ownstart()method. The base: