addEarlierSession method
Adds an earlier session of agentId in threadId with externalRef (/resume
chooses it).
Implementation
JsonMap addEarlierSession(
String threadId,
String agentId,
String externalRef,
) {
final s = _session(threadId, agentId, externalRef: externalRef)
..['is_current'] = false
..['ended_at'] = world.stamp()
..['end_reason'] = 'reset';
sessions.putIfAbsent(threadId, () => []).insert(0, s);
return s;
}