The ASIO session currently stores a source and destination endpoint that may have been parsed from an inbound connection speaking the proxy protocol. Currently, these values are only populated on mongos, but ASIO session is common to both mongod and mongos so it is expected that those same values will be populated once proxy protocol support is built into mongod.

We should expose an API to retrieve proxied endpoints and the "true" remote endpoint from transport::Session so that external subsystems (e.g., the Client) can use them.

Additionally, log these endpoints in the "Connection Accepted" (log 22943) mongos system log.