Convert SunCalc to ESModule export

[SamLeatherdale]

Pull Request Template for Home Assistant / Lovelace Card Repository

Overview

I am using this project as a submodule of my own HomeAssistant dashboard (HomeBoard)

There is an issue with importing SunCalc with Vite, where because it's a CommonJS export within an IIFE, it doesn't get picked up and I get the following error:

Uncaught SyntaxError: The requested module '/lovelace-horizon-card/suncalc3/suncalc.js' does not provide an export named 'default'

I have updated this module to use ES module syntax, and that resolves the issue.

Type of Change

• Bugfix
• New feature
• Enhancement
• Documentation update
• Refactoring
• Other (please describe):

Checklist

Please ensure that you have completed the following tasks before submitting your pull request:

• I have read the contributing guidelines for this project.
• I have tested my changes against the dev branch (or another appropriate branch) and verified that they are working as expected.
• I have updated the documentation (if applicable) to reflect my changes.
• My changes adhere to the repository's code style guidelines.
• My changes do not introduce any breaking changes or unexpected behaviors.

Related Issues / Pull Requests

Additional Details

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