fix: avoid false-positive overridden base warning when setting paths.base

[teemingc]

closes #15361

This PR changes the config hooks we have to run with order: 'pre' so that they don't override the base setting set by Vitest. If we run our config hooks earlier, Vitest doesn't try to set the base setting where we already have

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🦋 Changeset detected

Latest commit: 5154d66

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@sveltejs/kit	Patch

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[svelte-docs-bot]

Preview: https://svelte-dev-git-preview-kit-15623-svelte.vercel.app/

[teemingc]

/autofix