feat: reference kit types in ambient file

[mrkldshv]

Closes #5677. Includes reference to @sveltejs/kit types in ambient file, and removes reference from app.d.ts.

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[changeset-bot]

🦋 Changeset detected

Latest commit: 62c8cd1

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

This PR includes changesets to release 2 packages

Name	Type
create-svelte	Patch
@sveltejs/kit	Patch

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[mrkldshv]

Thanks for review! @dummdidumm @Conduitry

[Rich-Harris]

thank you!