refactor: enhanced-img with v-p-s6 preprocessor support

[dominikg]

This PR updates enhanced-img to the changes in vite-plugin-svelte that allow transforming svelte files

see https://github.com/sveltejs/vite-plugin-svelte/blob/main/docs/advanced-usage.md#transform-svelte-files-with-vite-plugins

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🦋 Changeset detected

Latest commit: 254841b

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

This PR includes changesets to release 1 package

Name	Type
@sveltejs/enhanced-img	Minor

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[benmccann]

@dominikg any reason this PR is marked as draft?

[dominikg]

because i wanted to wait until vite-plugin-svelte is released

[dominikg]

may also be good to test it a bit more, combine it with mdsvex again etc. I did some exploration and theory checks out but the test grabbing the transform handler directly is not covering plugin use.