[WIP] convert all files to ES Module format

[trusktr]

Summary

(WIP) convert all files to ESM.

What kind of change does this PR introduce?

Refactor

For any code change,

• [ ] Related documentation has been updated if needed
• [ ] Related tests have been updated or tests have been added

Does this PR introduce a breaking change? (check one)

• [ ] Yes
• [x] No

If yes, please describe the impact and migration path for existing applications:

Related issue, if any:

Tested in the following browsers:

[vercel[bot]]

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[trusktr]

Closing, making a new PR.