Type Alias ResponseMessage<T>

Union of all message types yielded by task-aware streaming APIs such as callToolStream(), ExperimentalClientTasks.requestStream(), and ExperimentalServerTasks.requestStream().

A typical sequence is:

1. taskCreated — task is registered (once)
2. taskStatus — zero or more progress updates
3. result or error — terminal message (once)

Progress notifications are handled through the existing onprogress callback. Side-channeled messages (server requests/notifications) are handled through registered handlers.