New field added to serverStatus output: network.totalTimeToFirstNonAuthCommandMillis (cumulative time from accepting an ingress connection to receiving the first command that isn't part of the auth handshake).

Description of Linked Ticket

Measure the time between the end of the authentication conversation and the reception of the first non-auth (non-sasl, authenticate, or hello) command on an ingress connection, and report it in a default-level log line.

Add a counter that tracks the cumulative time between the moment an ingress connection was accepted and the reception of the first non-auth command on it, and report it in serverStatus.