fix: account for min-width/height in slide transition

[Rich-Harris]

Supersedes #8907 (previous PR targets the svelte-4 branch and updates a no-longer-existent test), fixes #8533

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[changeset-bot]

🦋 Changeset detected

Latest commit: 9fd0340

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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Playground

pnpm add https://pkg.pr.new/svelte@14942