specify return type for node websocket create funciton

[jwetzell]

The kind of change this PR does introduce

• a bug fix
• a new feature
• an update to the documentation
• a code change that improves performance
• other

Current behavior

This error appeared when updating from v4.7.5 to v4.8.0 of socket-io-client

node_modules/engine.io-client/build/esm/transports/websocket.node.d.ts:12:101 - error TS1340: Module 'ws' does not refer to a type, but is used as a type here. Did you mean 'typeof import('ws')'?

12     createSocket(uri: string, protocols: string | string[] | undefined, opts: Record<string, any>): import("ws");
                                                                                                       ~~~~~~~~~~~~

Not sure why the type inference isn't working properly and websocket.node.d.ts does indeed specify the return type of that function as the whole of import("ws") which doesn't make sense as the error states.

New behavior

With the return type specified in websocket.node.ts transport the type declaration now looks like this.

import { WebSocket } from "ws";
import type { Packet, RawData } from "engine.io-parser";
import { BaseWS } from "./websocket.js";
/**
 * WebSocket transport based on the `WebSocket` object provided by the `ws` package.
 *
 * Usage: Node.js, Deno (compat), Bun (compat)
 *
 * @see https://developer.mozilla.org/en-US/docs/Web/API/WebSocket
 * @see https://caniuse.com/mdn-api_websocket
 */
export declare class WS extends BaseWS {
    createSocket(uri: string, protocols: string | string[] | undefined, opts: Record<string, any>): WebSocket;
    doWrite(packet: Packet, data: RawData): void;
}

Other information (e.g. related issues)

[darrachequesne]

Superseded by 175a2c5 (the return type was forced as any, so that the @types/ws dependency is optional).

Thanks 👍