feat: statically analyse universal pages and layouts v3

[eltigerchino]

closes #12580
closes #12578

Similar to #13669, we use acorn and acorn-ts to analyse the nodes. However, we follow the approach of #13673 where all exports (except load and exports prefixed with _) must have literal values or we fallback to importing the module. Then, we identify which nodes are never used for SSR by computing the final page options of each route beforehand. This allows us to avoid importing the module in Node and also avoid importing the component in the build output so that serverless function bundles don't include component code they will never use.

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Preview: https://svelte-dev-git-preview-kit-13684-svelte.vercel.app/