fix: Allow to disable animation prefix

[ai]

Fixes #14713

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[changeset-bot]

🦋 Changeset detected

Latest commit: f403c6f

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

This PR includes changesets to release 1 package

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svelte	Patch

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[Rich-Harris]

preview: https://svelte-dev-git-preview-svelte-14822-svelte.vercel.app/

this is an automated message

[github-actions]

Playground

pnpm add https://pkg.pr.new/svelte@14822

[paoloricciuti]

Thanks a lot 🙏🏻