fix: revert writing server files to the cloudflare build directory

[eltigerchino]

fixes #13621

This PR reverts the changes made in #13610 which causes the server-side dependencies to not be resolved correctly by Wrangler when it bundles the server files. In the first place, writing the server files to the build output wasn't useful since the dependencies aren't there too.

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🦋 Changeset detected

Latest commit: 163b6b4

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

This PR includes changesets to release 1 package

Name	Type
@sveltejs/adapter-cloudflare	Patch

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