Static site generator rewrite

[kevinkace]

Complete rewrite using Sveltekit.

• preview here: https://kevinkace.github.io/Local-Connectivity-Lab.github.io/
• i18n ready to go (currently only EN - https://github.com/kevinkace/Local-Connectivity-Lab.github.io/blob/svelte-ssg/messages/en.json)
• shared components for header, footer, buttons etc.
• updated some page routes, eg /aboutUs.html -> /about-us, sadly GH pages doesn't provide a mechanism for redirects, I had to add them client side, eg /aboutUs.html.
• added a favicon, some minimal visual polish and mobile responsive layout
• 404 and 500 error pages

fixes #12
fixes #15

[tedm]

The rewrite seems fine.

[kevinkace]

I ran Lighthouse, biggest issues were asset cache header time (nothing can be done about that when served from GitHub pages), and oversized images on mobile (#19)

Lighthouse desktop

Lighthouse mobile

[kevinkace]

⚠️ This will need to be set to be removed when merging - it was required to work with GH pages hosting without a custom domain.