task_state_to_status_update

def task_state_to_status_update(
    state: TaskState,
    *,
    task_id: str,
    context_id: str,
    message: Message | None = None,
    timestamp: datetime | None = None,
) -> A2ATaskStatusUpdate:
    """Build an ``A2ATaskStatusUpdate`` for a lifecycle transition.

    Used by the executor to surface ``start_work``/``complete``/``failed``
    transitions through the same A2AEvent layer that artifact updates
    use, instead of going through ``TaskUpdater`` directly.

    ``timestamp`` populates ``TaskStatus.timestamp``; pass ``None`` to
    let the wire stay empty (callers that want a real transition time
    should supply a ``datetime.now(tz=UTC)``).
    """
    status_kwargs: dict[str, Any] = {"state": state}
    if message is not None:
        status_kwargs["message"] = message
    if timestamp is not None:
        status_kwargs["timestamp"] = timestamp
    status = TaskStatus(**status_kwargs)
    update = TaskStatusUpdateEvent(task_id=task_id, context_id=context_id, status=status)
    return A2ATaskStatusUpdate(update=update, state=state)