Fix hidden pages in sitemap exports

[rodrcastro]

Summary

• Include hidden-but-indexable pages in llms.txt, llms-full.txt, and sitemap page exports
• Preserve ancestor-aware noIndex / noRobotsIndex filtering
• Add regression coverage for hidden pages and nested group traversal

Testing

• bun test packages/gitbook/src/lib/sitemap.test.ts
• bun run format
• cd packages/gitbook && bun run typecheck

Fixes RND-10663

[changeset-bot]

⚠️ No Changeset found

Latest commit: c28fd2c

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[github-actions]

Summary of the deployments:

Version	URL	Status
Vercel	https://gitbook-v2-cg4r8fuqu-gitbook.vercel.app	✅
Cloudflare	https://32bbf0c2-gitbook-open-v2-preview.gitbook.workers.dev	✅

Test content

Site	2v	2c
GitBook	https://gitbook-v2-cg4r8fuqu-gitbook.vercel.app/url/gitbook.com/docs	https://32bbf0c2-gitbook-open-v2-preview.gitbook.workers.dev/url/gitbook.com/docs
E2E	https://gitbook-v2-cg4r8fuqu-gitbook.vercel.app/url/gitbook.gitbook.io/test-gitbook-open	https://32bbf0c2-gitbook-open-v2-preview.gitbook.workers.dev/url/gitbook.gitbook.io/test-gitbook-open

[argos-ci]

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Build	Status	Details	Updated (UTC)
customers-v2-cloudflare (Inspect)	✅ No changes detected	-	Apr 30, 2026, 12:57 PM
customers-v2-vercel (Inspect)	✅ No changes detected	-	Apr 30, 2026, 12:57 PM
v2-cloudflare (Inspect)	👍 Changes approved	13 changed	Apr 30, 2026, 1:02 PM
v2-vercel (Inspect)	👍 Changes approved	20 changed	Apr 30, 2026, 1:03 PM

[linear]

RND-10663 Hidden page missing from llms-full.txt