Function router_daemon_with_arrow 

pub fn router_daemon_with_arrow(
    state: AppState,
    auth: AuthConfig,
    max_payload_bytes: usize,
    rate_limiter: RateLimiter,
    playground: bool,
    arrow: bool,
) -> Router

Build the daemon router with the unofficial Arrow endpoint explicitly enabled. arrow = false has the same behavior as router_daemon.