[fix] restart on config change

[dominikg]

recently sveltekit changed to passing the svelte config inline to vite-plugin-svelte. With this way, vite-plugin-svelte does not watch svelte.config.js for changes to restart the vite devserver, as configFile: false indicates it should not use it.

this PR sets up a watcher in kits dev plugin that does the same. Restarting the server is absolutely required in this case.

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Latest commit: a721b0c

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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