docs: Add guidance for usage with Deno bundler

With Deno there are a couple extra steps to consume Excalibur to bundle a game for the browser.

esm.sh should generate a bundle that works, tested locally.

deno info https://esm.sh/excalibur

type: JavaScript
dependencies: 180 unique (total 816KB)

https://esm.sh/excalibur (192B)
├── https://cdn.esm.sh/v54/excalibur@0.25.0/deno/excalibur.js (355.24KB)

Outputs a bundle:

deno bundle https://esm.sh/excalibur excalibur.bundle.js

Using native in browser

Using as a native module works in Chrome without any extras:

<script type="module">
  import ex from "./excalibur.bundle.js";

  const game = new ex.Engine();
  game.start();
</script>

Using with bundler

More likely users will be writing a game and will be importing Excalibur. Deno uses URLs so we’ll want to showcase pinning.

A custom tsconfig.json has to be used with strict turned off and there are a few DOM libs to add:

tsconfig.json

{
  "compilerOptions": {
    "strict": false,
    "lib": ["dom", "dom.iterable", "dom.asynciterable", "deno.ns"]
  }
}

Then Excalibur can be imported from esh.sh:

index.ts

import { Engine } from "https://esm.sh/excalibur";

const game = new ex.Engine();
game.start();

And Deno will successfully bundle:

deno bundle index.ts game.bundle.js --config tsconfig.json

Check file:///E:/Development/Junk/deno-excalibur/index.ts
Bundle file:///E:/Development/Junk/deno-excalibur/index.ts
Emit "game.bundle.js" (678.91KB)

Thanks to @tarsupin for bringing this up.

_Originally posted by @kamranayub in https://github.com/excaliburjs/Excalibur/discussions/2060#discussioncomment-1480720_

[Return180bpm]

@kamranayub, @eonarheim: This was my first PR. Thank You for all your help!

[kamranayub]

Thanks, those will be fixed in an upcoming PR I am working on that will upgrade our dependencies