default-exports: Refactor rule to handle meta declaration

[yannbf]

Issue: #

What Changed

The default-exports rule now supports auto-adding export default when users have only typed:

const meta = {}

so it will become

const meta = {}
export default meta

Checklist

Check the ones applicable to your change:

• Ran pnpm run update-all
• Tests are updated
• Documentation is updated

Change Type

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• maintenance
• documentation
• patch
• minor
• major