fix: resolve config paths only after we have root

[teemingc]

This PR separates the config processing from the validation because the processing needs to happen after we've retrieved the Vite root value. This is important for proper monorepo support. Otherwise, tooling such as our language tools and Vitest end up resolving file paths relative to where the process started rather than relative to the project root

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[pkg-svelte-dev]

Install the latest version of @sveltejs/kit from eea4652:

pnpm add https://pkg.svelte.dev/@sveltejs/kit/c/eea46521d0061e06db4edfeff422ece1380e5161

Open in pkg.svelte.dev: https://pkg.svelte.dev/repos/kit/pr/16229

[changeset-bot]

🦋 Changeset detected

Latest commit: eea4652

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

This PR includes changesets to release 1 package

Name	Type
@sveltejs/kit	Patch

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[svelte-docs-bot]

Preview: https://svelte-dev-git-preview-kit-16229-svelte.vercel.app/