Function rest_availability_service_stream_transactions 

async fn rest_availability_service_stream_transactions<S>(
    __arg0: State<Arc<S>>,
    headers: HeaderMap,
    __arg2: Query<StreamTransactionsRequest>,
) -> Result<Sse<impl Stream<Item = Result<Event, Infallible>>>, RestError>
where
    S: AvailabilityService + Send + Sync + 'static,

StreamTransactions - SSE streaming endpoint.

GET /v2/availability/stream/transactions → text/event-stream