The Claude Design Send-to guide rendered at its URL but was an orphan — absent from the
docs nav and llms.txt, so it never surfaced as a fetchable search RESULT (only as body
text in another page's excerpt, which Claude Design's web_fetch rejects). Add it to the
Guides nav (→ llms.txt index) next to claude-design, and give it frontmatter title +
description for a clean entry. This makes the full guide discoverable + fetchable via
search, the reliable path since a URL named only in a tool description is not fetchable.