breaking: require SvelteKit 2 for all adapters

[dummdidumm]

Bumping all the adapters to require SvelteKit 2, because a) esbuild changes and we want to be careful b) easier to do minors using new capabilities c) adapter-auto is more robust in installing correct versions then

No changeset for the migration script because that's not released yet.

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🦋 Changeset detected

Latest commit: a4795d8

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

This PR includes changesets to release 4 packages

Name	Type
@sveltejs/adapter-cloudflare-workers	Major
@sveltejs/adapter-cloudflare	Major
@sveltejs/adapter-netlify	Major
@sveltejs/adapter-auto	Major

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