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 Create web based report of test runner #678 machinery to visualise diffs to test cases for a PR
• Should wait until Introduce tree-sitter queries for syntactic scopes #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

See also #1524; we'll probably want a web representation for these test cases as well

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