fix: avoid marking subtree as dynamic for inlined attributes

[paoloricciuti]

Closes #14241 (this time for real...i don't think we can get less than this but happy to be proved wrong by @benmccann 😄 )

I've restructured the code a bit to have a shared utils.

Also fixes #14292

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🦋 Changeset detected

Latest commit: 61b60ab

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

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[Rich-Harris]

preview: https://svelte-dev-git-preview-svelte-14269-svelte.vercel.app/

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[github-actions]

Playground

pnpm add https://pkg.pr.new/svelte@14269

[paoloricciuti]

Also for some reason when i tried to import extract_all_identifiers_from_expression it was not able to run the playground anymore 🤷🏼

[paoloricciuti]

@Rich-Harris obviously thanks for taking care of solving this...I suspected something was very wrong (I can't be at the desk now but please let me know if I need to do something) 🤟🏻