replicationReady property
replicationReady instructs the server to emit a system event once the
Postgres replication connection backing this channel is established and
ready to stream changes.
Listen for it with RealtimeChannel.onSystemEvents; the payload's
RealtimeSystemPayload.status is 'ok'
(message: 'Replication connection established') on success or 'error'
if the connection is not ready in time.
Implementation
final bool replicationReady;