Add support for TypeScript

[rauschma]

Someone who knows more about .d.ts files and packages should probably take a look at what I have set up. I’ll ask on Mastodon.

• I tested the setup locally via a TypeScript repo and npm add ../regex and the types worked.
• dist/regex.min.js should maybe be included in the package exports in some way.
• You may want to clear dist/ before "build" and types/ before "types". I’m using package shx for cross-platform shell commands.
• Maybe:
  • Rename "build" to "esbuild"
  • Define "build" as "npm run esbuild && npm run types"
• I don’t know whether or not "typescript" should become a devDependency.
• @overload is another option for overloading regex but I’m not sure in which of the multiple JSDoc comments the actual documentation would go.
  • Benefit of @overload: It may help with specifying this for regex. I don’t know how to best do that. I avoid using this as an implicit parameter in my code.

Command for checking if the types are correct (potential addition to package.json "scripts"):

npx --package=@arethetypeswrong/cli attw .

[slevithan]

Thanks for the PR, @rauschma!! I'm traveling for the next couple days but will follow up on this shortly after.