fix: silence assignment warning on more function bindings

[dummdidumm]

fixes #15550

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[changeset-bot]

🦋 Changeset detected

Latest commit: 664ac7f

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

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svelte	Patch

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[svelte-docs-bot]

Preview: https://svelte-dev-git-preview-svelte-15644-svelte.vercel.app/

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Playground

pnpm add https://pkg.pr.new/svelte@15644