Add ESM build output and improve package exports for better module compatibility

[MTroian94]

Merge request about this issue #130

[MTroian94]

@TheSGJ do you have any update?

[marcoreni]

Hey @TheSGJ do you have an estimated timeline for merging this? It doesn't seem a distructive change to me

[Copilot]

Pull Request Overview

This PR adds ESM (ECMAScript Module) build output alongside the existing CommonJS format to improve module compatibility for modern JavaScript environments. The changes enable dual-format publishing to support both import and require syntax.

Key changes:

• Adds ESM format to the build configuration
• Updates package.json exports to support both ESM and CommonJS formats
• Adds explicit module entry point for ESM consumers

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
tsup.config.ts	Adds ESM format to build output alongside existing CJS
package.json	Updates exports map to support dual module formats and adds module field

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[TheSGJ]

@TheSGJ do you have any update?

Hey, so sorry for the delayed reply. This code looks good for implementing ESM support.

I will now merge these changes.

[TheSGJ]

[Error: Cannot find module '.../node_modules/next/router' imported from .../node_modules/nextjs-toploader/dist/pages.mjs
Did you mean to import "next/router.js"?] {
  code: 'ERR_MODULE_NOT_FOUND',
  url: 'file:///.../node_modules/next/router'
}

Seems to be a problem with the ESM export.

Originally posted by @Daniel3711997 in #138

I will revert this PR as it seems to be causing issues with ESM export support. Will look into this again later