Issue importing libheif as described in the docs.

[boustanihani]

According to the docs, libheif hast to be imported like this:
https://github.com/catdad-experiments/libheif-js?tab=readme-ov-file#usage

<script type="module">
        import libheif from 'https://cdn.jsdelivr.net/npm/libheif-js@1.19.8/libheif-wasm/libheif-bundle.mjs';
</script>

But this does not work (in the browser console, libheif is a function).
It only works if I add window.libheif = libheif(); to the statement, why is that?

<script type="module">
        import libheif from 'https://cdn.jsdelivr.net/npm/libheif-js@1.19.8/libheif-wasm/libheif-bundle.mjs';
        window.libheif = libheif();
</script>