Add Service Worker examples to Open Web demos

[jcubic]

Description

Add two demos to the list of Open Web technologies demos

Motivation

It showcases different use of Service Worker

Additional details

• Both demos create HTML pages from Service Worker

[github-actions]

Preview URLs

• /en-US/docs/Web/Demos

External URLs (2)

URL: /en-US/docs/Web/Demos
Title: Demos of open web technologies

• https://jcubic.github.io/wayne/code/ (1 time) (Note! This may be a new URL 👀)
• https://jcubic.github.io/wayne/offline/ (1 time) (Note! This may be a new URL 👀)

[skyclouds2001]

Maybe CSS custom highlight API is more suitable

[jcubic]

You will need to create a library for syntax highlighting first. And still, you will need to use Service Worker to create the HTML page so you can include the JavaScript code.