pub type ReplicaViewRow = (String, Ipv4Addr, u16, u64, Option<ReplicaAck>);Expand description
One replica conn’s row in the per-tick replication view:
(replica_id, peer_ipv4, peer_port, sent_offset, ack). The id is
the identity string the replica presented at handshake — command
layers group per-shard rows by it to render one aggregate entry
per replica process.