Create web page to represent test cases

[pokey]

The problem

Along the lines of #678, it would be useful to be able to see our test cases in a web representation. This view would enable us to be a bit more terse with the actual representation we use for the test cases, while making the tests easier to view.

Some thoughts

• [ ] Combined with deploy previews, it gives us a nice way to see new test cases
• [ ] Could possibly use #678 machinery to visualise diffs to test cases for a PR
• [ ] Should wait until #629 merges so that we can visualise domain, removal range, iteration scope, etc
• [ ] Should be based on new test cases that visualise query ranges as above
• [ ] Could actually expose these under cursorless.org/tests, as they form a kind of documentation. Might also integrate them into our actual docs

Resources

• https://github.com/FormidableLabs/prism-react-renderer
• https://github.com/react-syntax-highlighter/react-syntax-highlighter
• https://github.com/wooorm/refractor
• https://github.com/rexxars/react-refractor/blob/main/src/addMarkers.js
• https://prismjs.com/plugins/show-invisibles/
• https://github.com/PrismJS/prism/blob/de79636a8a146300436a184b443594528d43aafe/plugins/data-uri-highlight/prism-data-uri-highlight.js