fix: disallow export { foo as default } in <script module>

[Ocean-OS]

Currently, the compiler will throw an error if you use export default in a component.
However, it doesn't throw if you use export { foo as default } or export { foo as 'default' }. This fixes that.

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Tests and linting

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[github-actions]

Playground

pnpm add https://pkg.pr.new/svelte@16447

[7nik]

Shouldn't it have a test? There are already validator/default-export-* tests for this behavior.

[changeset-bot]

🦋 Changeset detected

Latest commit: d0d1bfd

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
svelte	Patch

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