Function websockets

Returns {
    closeBundle: { handler: () => void; order: "post"; sequential: true };
    configurePreviewServer: (
        server: {
            httpServer?:
                | {
                    on(
                        event: "upgrade",
                        listener: (req: IncomingMessage, socket: Duplex, head: Buffer) => void,
                    ): void;
                }
                | null;
        },
    ) => void;
    configureServer: (
        server: {
            httpServer?:
                | {
                    on(
                        event: "upgrade",
                        listener: (req: IncomingMessage, socket: Duplex, head: Buffer) => void,
                    ): void;
                }
                | null;
        },
    ) => void;
    name: string;
}