fix: extend Svelte Config type

[teemingc]

This PR changes our Config type to extend the VPS Config type instead of trying to duplicate it like we are now.

TODO:

• check that the options are consistent with the user's installed VPS rather than the version we've installed in our Kit repo

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[changeset-bot]

🦋 Changeset detected

Latest commit: 3b26193

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-13982-svelte.vercel.app/

[dummdidumm]

Just to double-check, these types exist in the correct way since the vps version that we have a peer dep on, right?

[teemingc]

Just to double-check, these types exist in the correct way since the vps version that we have a peer dep on, right?

Yes. I tested this by installing this PR into a new SvelteKit project.

One thing to think about is how to link to the VPS config type and let people know it's based on their VPS version in https://svelte-dev-git-preview-kit-13982-svelte.vercel.app/docs/kit/configuration#Config . Should we explain it in the Config type's JSDoc or mention it here?

kit/documentation/docs/98-reference/50-configuration.md

Lines 29 to 31 in 537d33e

	## Config
	> TYPES: Configuration#Config

[dominikg]

SvelteConfig is exported by v-p-s@3 which is the lowest version sveltekit supports.
However i'm not sure if this https://github.com/sveltejs/vite-plugin-svelte/blob/9fab1303820d6219f97ff8e365807785e21af5c6/packages/vite-plugin-svelte/types/index.d.ts#L3 worked for svelte@4, digging into that now

[dominikg]

looks like it works, setting up an old kit project via pnpm create svelte@6 and linking this branch

devDependencies:
@sveltejs/kit file:../../sveltejs/kit/packages/kit(@sveltejs/[email protected]([email protected])([email protected](@types/[email protected])))([email protected])([email protected](@types/[email protected]))
@sveltejs/vite-plugin-svelte 3.1.2
svelte 4.2.20
is 📦 v0.0.1 via  v22.17.0 
develop/reproductions/old-kit ❯ tsc --allowJs --checkJs --skipLibCheck --noEmit svelte.config.js
is 📦 v0.0.1 via  v22.17.0 
develop/reproductions/old-kit ❯ 

i had to install @types/node and set up a tsconfig.json that covers svelte.config.js to make it work

[dominikg]

Not getting autocomplete for onwarn in intellij, but works in vscode