refactor: prettier-config from json to js

[grantwforsythe]

This was done so that the base config is extensible which will allow other projects to install any prettier plugins that might be relevant for their project, e.g. prettier-plugin-tailwind.

[spike-rabbit]

I think this makes sense 👍

Just one additional note regarding the commit note. I think in the scope of this repository, this change is a feature. So a commit message like this would be nicer:

feat(prettier-config): additionally export config as .js

Unlike the current .json config, the .js config can be imported and
extended.

Please also update the README.md to show this way of using it:

"prettier": "@siemens/prettier-config", (without /.prettierrc.json)

[spike-rabbit]

this breaks current configuration. Since I do not see any reason for the *.md export I think we could do this:

  "exports": {
    ".": "./index.js",
    "./.prettierrc.json": "./.prettierrc.json"
  },

That way you can use this in your app as:

{
  "prettier": "@siemens/prettier-config",
}

[grantwforsythe]

Given that there is only one entry point in to the package, we can just remove .prettierrc.json and use main which has a default value of index.js

[spike-rabbit]

yes, but this is breaking the current way of using it.

Projects currently have prettier: '@siemens/prettier-config/.prettierrc.json'. This will stop working if we no longer export this in the package.json. So the idea would be to keep both for a while until we anyway need to break things. Then we can remove the prettierrc.json and the related export.

[grantwforsythe]

That sounds reasonable to me. I have added back the rc file