Add ES modules (ESM) support

[RabeeAbuBaker]

Thank you for this awesome repo!!

I get this error after Importing AtButton into an ESM project ("type": "module")

import { AtButton } from "vite-component-library-template";
         ^^^^^^^^
SyntaxError: Named export 'AtButton' not found. The requested module 'vite-component-library-template' is a CommonJS module, which may not support all module.exports as named exports.
CommonJS modules can always be imported via the default export, for example using:

import pkg from 'vite-component-library-template';
const { AtButton } = pkg;

    at ModuleJob._instantiate (node:internal/modules/esm/module_job:124:21)
    at ModuleJob.run (node:internal/modules/esm/module_job:190:5)

[RabeeAbuBaker]

I was able to fix this by simply adding "type": "module" to package.json

[IgnacioNMiranda]

Hey! would you mind creating a PR with the change and an explanation? please also check if it creates any issue for other kind of deployments (: