Add a new dev command to improve interactive development

[robert-j-webb]

Hi,

I appreciate the repo, I thought I'd contribute back a suggestion that I find is helpful. I recommend this start script:

package.json

  "scripts": {
    "start": "tsx watch src/main.ts",

or you may want to name it dev instead. Either way, it means you have a nice, interactive dev experience. You also need to add tsx to dev deps like:

    "tsx": "^4.20.6",

If you've already considered this, no worries, just thought I'd leave a suggestion.

[robert-j-webb]

Also a different issue, but having the prettierrc file contain parser: "typescript" should be unnecessary and causes issues if you have a non-typescript file

See docs: https://prettier.io/docs/options#parser