Function serve_generator 

pub fn serve_generator<T>(t: T, socket: impl Into<SocketAddr>) -> JoinHandle<()>
where
    T: MetadataGenerator + Send + Sync + 'static,

Serve an NFT generator at the specified socket address.

Adds routes for /:token_id and /, as well as a fallback 404. This is a simple, works-out-of-the-box JSON metadata server with no additional app or routing customization. If you would like to add additional routes, consider defining the axum Router and handlers separately, and passing your router to serve_router