Check code that uses consensus membership to find clients
In legacy/trac#21406 (moved), we identify clients by checking peer authentication information, as CREATE_FAST has been phased out.
Most code that needs to know if the other end of a connection is a client uses membership in the consensus, but this is unreliable, as relays drop out of the consensus.
So we should check code that uses node_t to identify clients, and switch it over to using this flag instead.
This might mean creating an accessor function that takes an or_connection_t and returns whether the channel is a client.