Edit a campaign's settings

A draft or needs_review campaign accepts every setting. A scheduled or paused campaign accepts the run-safe settings only: name, from_number_ids, time_zone_mode, time_zone, calling_windows, retry_policy / retry_policy_preset, max_concurrency, reserved_concurrency, ends_at and language, plus scheduled_start_at while still scheduled. Agent, contact list, purpose and consent basis are locked after launch (duplicate the campaign to change them); a running campaign must be paused first. The edit is serialized with the dispatcher and with pause/resume/cancel: a concurrent status change answers 409. Changing the calling windows or zone re-evaluates contacts that were waiting for the old window on the next tick. The response is the campaign plus changed, the list of settings that actually changed.