feat: statically analyse universal pages and layouts

[eltigerchino]

closes #12580

Based off @benmccann 's suggestion, this PR uses static analysis to retrieve literal values from the universal module without importing it on the server. Instead, we only import the module on the server if a non-literal value is accessed such as the load function or a value that can only be determined at runtime. This allows developers to use browser APIs in their universal pages and layouts if they have export const ssr = false.

It also logs the reason we load a module if it fails to load (e.g., trying to access export X or not being able to statically analyse all exports). The only exception is during build and a module re-exports all named exports from another module because we can't use top-level await to dynamically import the module and catch the import error.

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🦋 Changeset detected

Latest commit: 1af9eda

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

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[svelte-docs-bot]

Preview: https://svelte-dev-git-preview-kit-13669-svelte.vercel.app/

[eltigerchino]

closing in favour of #13684