fix(perf): correctly apply id filter in enhanced:img

[dominikg]

Without this change, no id filter is active in enhanced-img, leading to all files being checked with the code regex.
If a file that isn't a svelte file contains <enhanced:img this can cause build errors too (discovered during dependency update in svelte.dev repo)

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Latest commit: acd4339

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Name	Type
@sveltejs/enhanced-img	Patch

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