fix: use ESM chunkLoading for "esm" format

[fi3ework]

Summary

Fix #254.

Related Links

Checklist

• Tests updated (or not required).
• Documentation updated (or not required).

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[codspeed-hq]

CodSpeed Performance Report

Merging #256 will not alter performance

_{Comparing async-chunk (e5a266d) with main (d1be3a7)}

Summary

✅ 2 untouched benchmarks

[Timeless0911]

What if the target is web instead of node?

[fi3ework]

@Timeless0911 Same, but I don't think this will work for typical web scenes. Due to webpack/webpack#15697, the dynamic chunk can't be bundled it can't be statically resolved. It has been tracked in #45.