Fix rendering when the syntaxHighlight plugin is not installed

7e2b83af2ca3ff4ff26a0850c9f8238ae8215097

Tucker McKnight <tmcknight@instructure.com> | Sun Jul 19 2026

Fix rendering when the syntaxHighlight plugin is not installed

When syntax highlighting isn't available, it needs to return an escaped
string with pre tags around it. This means it will show whitespace in
plain text, and also *not* render HTML components on the page when it
should be just showing the HTML code.

Fix the path to CSS and JS files, which wasn't working when using a root
path before.

I've removed the call to eleventyConfig.addTemplateFormats("js"), which didn't
seem to be doing anything. I had to add eleventyConfig.addTemplateFormats("11ty.js")
to the site using this plugin for it to work -- maybe add that instead?

Add a todo about not including the prism css file if it's not being used. Also,
need to allow users to provide their own prism file.