* docs: clarify preview API does not support fork branches
* docs: translate fork preview clarification and tighten SEO description
* Apply suggestion from @ethanpalm
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Co-authored-by: mintlify[bot] <109931778+mintlify[bot]@users.noreply.github.com>
Co-authored-by: Ethan Palm <56270045+ethanpalm@users.noreply.github.com>