fix: allow async destructured deriveds

[Ocean-OS]

Closes #16442

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[changeset-bot]

🦋 Changeset detected

Latest commit: 64e4a4b

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

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svelte	Patch

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Playground

pnpm add https://pkg.pr.new/svelte@16444 

[Rich-Harris]

oops, meant to commit this in a separate PR. oh well never mind