[fix] reuse server data while not reusing client load

[dummdidumm]

Fixes #6459
Closes #6641

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🦋 Changeset detected

Latest commit: 1a31eac

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

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@sveltejs/kit	Patch

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[mquandalle]

This will also close #6641

[benmccann]

@dummdidumm FYI, the test failure on this one appears to be a real one