Function collect_routes_until_idle

pub async fn collect_routes_until_idle<I: FidlRouteIpExt, C: Extend<InstalledRoute<I>> + Default>(
    event_stream: impl Stream<Item = Result<Event<I>, WatchError>> + Unpin,
) -> Result<C, CollectRoutesUntilIdleError<I>>

Collects all existing events from the stream, stopping once the idle event is observed.