[Bug]: Node16 moduleResolution error when building custom package

[tspng]

Bug description

Hi, I was about to create a custom plugin.
Trying to build a custom build (tom-select.custom.js) fails with the following error:

> tom-select@2.4.3 build
> grunt build --plugins=remove_button,restore_on_backspace

... snip uninteresting parts ...

> tom-select@2.4.3 build:js:esm
> tsc -p .config/tsconfig.esm.json

src/tom-select.custom.ts(2,23): error TS2835: Relative import paths need explicit file extensions in ECMAScript imports when '--moduleResolution' is 'node16' or 'nodenext'. Did you mean './tom-select.js'?
Warning: Command failed: npm run build:js
 Use --force to continue.

Aborted due to warnings.

The issue is that the generated tom-select.custom.ts imports ./tom-select without the .js extension.
It's an easy fix and I can create a PR if interested.

Expected behavior

Running npm build with the --plugins option should complete successfully without TypeScript errors.

Steps to reproduce

1. Clone the repo, get on master branch
2. Run npm install
3. Run npm run build -- --plugins=remove_button,restore_on_backspace
4. See error: TS2835: Relative import paths need explicit file extensions in ECMAScript imports when '--moduleResolution' is 'node16' or 'nodenext'

Additional context

• OS: macOS 15.5

[nwalters512]

A PR would be welcome here! I actually didn't know that the build system supported this.

[tspng]

It is the build process described here:

tom-select/doc_src/pages/docs/plugins.md

Lines 70 to 84 in 4522c18

	#### tom-select.custom.js
	Use NPM to hand-pick plugins and create <code>/dist/js/tom-select.custom.js</code>
	```shell
	# clone the repo
	git clone https://github.com/orchidjs/tom-select.git
	cd tom-select
	# install dev dependencies
	npm install
	# create /dist/js/tom-select.custom.js
	npm run build -- --plugins=remove_button,restore_on_backspace
	```

However, it only creates a custom Javascript build.
The css still contains all the styles and all the plugins' styles files are statically imported in the main .scss file.

One could argue if this custom build is even needed as there aren't many plugins included.