fix: migration fixes

[dummdidumm]

• add $state rune at correct location, fixes Svelte 5 migration: Transformed declarations with TS annotations cause broken output #12171
• correctly indent event handlers, fixes Svelte 5 migration: event modifier transformer doesn't respect indentation #12170

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[changeset-bot]

🦋 Changeset detected

Latest commit: f3a8de7

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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