Receive Ports, Receive Locations, and what arrives at them: the
ReceiveLocation with its transport, its address and its identity policy,
the ReceivePort that binds arrivals into the topology, and the
ReceivedStream a transport hands over.
Receive owns inbound orchestration and nothing about how bytes move: a transport technology moves the Stream, this crate decides what is done with it. It does not create the Message — a Contract accepts a Stream — and it does not send. A Receive Location declares a closed set of mechanisms and Parties it accepts; anything else is refused at authentication (ADR-0019).
doc/architecture/runtime-model.md sections 5 and 6 govern the receive
chain, ADR-0010 the boundary with transport; architecture.toml carries the
maturity.