docs(readme): added node.js example

[ShanTen]

Including the Node.js code snippet directly in the README would be convenient for quick reference.

[miquelfire]

There is a push to switch to use ESM, so using import instead of require might be better.

Actually, I think it would be better to have the require/import lines in the NPM and Yarn sections

[ShanTen]

So something like..?

🚀 Getting started

yarn:

yarn add sqids

npm:

npm install sqids

cdnjs:

<script src="https://cdnjs.cloudflare.com/ajax/libs/sqids/0.3.0/sqids.min.js"></script>

jsDelivr:

<script src="https://cdn.jsdelivr.net/npm/sqids/dist/sqids.min.js"></script>

🛠️ Using Sqids in Node.js

CJS:

const Sqids = require('sqids').default;

const sqids = new Sqids({
    blocklist: new Set(['86Rf07']),
});

ES6:

import Sqids from 'sqids';

const sqids = new Sqids({
  blocklist: new Set(['86Rf07']),
});

👩‍💻 Examples

...

[miquelfire]

I'm thinking that's too busy. Over all, you just need the import/require lines, maybe at the top of the Examples. Maybe something like this (I don't like the heading I used here):

👩‍💻 Examples

Node.js import:

// ESM
import Sqids from 'sqids';

// CJS
const Sqids = require('sqids').default;

Simple encode & decode:

[4kimov]

@ShanTen @miquelfire I think I've been doing so many of these READMEs in diff languages, that I totally forgot about the import statement (and it should be there). I'll just use esm for now to keep it simple and close the PR, but thanks for the heads up!