Add `"type"="module"` to package.json or export `.mjs` file

[robinscholz]

Hi xiel,

woudl you consider adding "type"="module" to the package.json, seeing as ESM is pretty much the way forward for the JS ecosystem? I finally moved the dependency back to this package from our fork and ran into some issues with Vite and SSR today.

From the Node docs:

Node.js will treat the following as ES modules when passed to node as the initial input, or when referenced by import statements or import() expressions:

• Files with an .mjs extension.

• Files with a .js extension when the nearest parent package.json file contains a top-level "type" field with a value of "module".

The esm export of wheel-gestures uses .esm.js as its extension, which does not get picked up by node and results in vite thinking its a common js module when trying to build the server bundle.

You could either change the filename of the esm build to wheel-gestures.mjs or add "type"="module" to the package.json.

Thanks again for making the suggested changes with the exports field!