chore: revert dev error when using use:enhance with +server

[eltigerchino]

This PR reverts #13197 since it cause an error for users that used SuperForm's helper that made +server responses compatible with use:enhance.

EDIT: In hindsight, we should probably update the use:enhance docs https://svelte.dev/docs/kit/form-actions#Progressive-enhancement to explain that it should only be used with SvelteKit form actions to address the original issue.

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🦋 Changeset detected

Latest commit: 09580d5

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

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@sveltejs/kit	Patch

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[svelte-docs-bot]

Preview: https://svelte-dev-git-preview-kit-13397-svelte.vercel.app/

[ciscoheat]

Thank you! :)