Function drive_conversation_stream 

pub async fn drive_conversation_stream<S, F>(
    stream: S,
    on_event: F,
) -> Result<ConversationResponse>
where
    S: Stream<Item = Result<ConversationStreamEvent>> + Send + Unpin,
    F: FnMut(ConversationStreamEvent) + Send,

Drive a conversation event stream to completion, invoking on_event for every event, and returning the final ConversationResponse once a ConversationStreamEvent::WorkflowFinished or ConversationStreamEvent::HumanInteractionRequired event is observed (or an error if the stream ends before either happens). An interrupted run emits HumanInteractionRequired instead of WorkflowFinished, never both, so exactly one of the two is expected per run.

Used by binding layers that are call-scoped-callback shaped (C, C++, Node.js) — every other binding either pulls synchronously (conversation_stream_iter) or drives with real backpressure (ConversationStreamSubscription).