Function ask_with_provider 

pub fn ask_with_provider<P: Provider>(
    conn: &Connection,
    question: &str,
    config: &AskConfig,
    provider: &P,
) -> Result<AskResponse, AskError>

Lower-level entry point — same flow, but you supply the provider.

Used by the test suite (which passes a MockProvider) and by advanced callers who want to drive a custom backend (an internal LLM gateway, a recorded-replay test harness, etc.).