Lit-aware major modes for JavaScript and TypeScript that use the
`lit-html' tree-sitter grammar (from github.com/ispringle/tree-sitter-lit-html)
instead of standard `html', and add completion for CSS classes/IDs
across `html'/`css' tagged template literals.

Requires Emacs 30+ with tree-sitter support and the javascript,
typescript, css, and lit-html grammars installed.

Usage:
  Use `lit-ts-js-mode' instead of `js-ts-mode'
  Use `lit-ts-typescript-mode' instead of `typescript-ts-mode'