fix: improve animation name transformation

[navorite]

closes #10189, #9879

Svelte 5 rewrite

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[changeset-bot]

🦋 Changeset detected

Latest commit: bbc707f

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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[Rich-Harris]

thank you!