Calling window. Outside the agent’s window the call is accepted and
scheduled_for says when it dials.
Status: queued → dialling → completed · no_answer · busy · failed · canceled.
Results: outcome, summary, final_variables on the call; GET /v1/calls/{id}/transcript, /analysis, /recording.
Stop it: DELETE /v1/calls/{id} (queued) · POST /v1/calls/{id}/hangup (live).
Webhooks: call.ended, then call.analyzed.