Function run_statement 

pub async fn run_statement<T: StatementTransport>(
    cx: &Cx,
    client: &T,
    auth: AuthorizationDescriptor,
    request: SubmitStatementRequest,
    params: SubmitQueryParams,
    poll_plan: PollPlan,
) -> StatementOutcome

Submit a statement and drive it to completion: submit -> poll/await -> partition fetch -> assemble, firing the remote cancel endpoint if the ambient Cx is cancelled mid-flight.

request is the SQL API submit body; params carries the idempotency requestId/retry query contract that makes a resubmit safe.