docs: add custom admin route ranking documentation

[bqst]

Summary

What — What changes are introduced in this PR?

Related PR #13946
Add custom admin route ranking documentation

Why — Why are these changes relevant or necessary?

Please provide answer here

How — How have these changes been implemented?

Please provide answer here

Testing — How have these changes been tested, or how can the reviewer test the feature?

Please provide answer here

---

Examples

Provide examples or code snippets that demonstrate how this feature works, or how it can be used in practice.
This helps with documentation and ensures maintainers can quickly understand and verify the change.

// Example usage

---

Checklist

Please ensure the following before requesting a review:

• I have added a changeset for this PR
  • Every non-breaking change should be marked as a patch
  • To add a changeset, run yarn changeset and follow the prompts
• The changes are covered by relevant tests
• I have verified the code works as intended locally
• I have linked the related issue(s) if applicable

---

Additional Context

Add any additional context, related issues, or references that might help the reviewer understand this PR.

---

Note

Adds admin UI docs for sidebar route ranking (including nested), sorting rules, and examples using CodeTabs; mirrors updates in the public content file.

• Docs (Admin UI Routes) in www/apps/book/app/learn/fundamentals/admin/ui-routes/page.mdx:
  • Add rank property to defineRouteConfig docs and explain sidebar ordering.
  • New section: "Specify UI Route Sidebar Rank" with version note (v2.11.4).
  • Add sorting rules for ranked vs. unranked routes.
  • Add "Nested UI Routes Ranking" with examples under orders.
  • Provide two example routes (Analytics, Reports) demonstrating rank via CodeTabs/CodeTab (and import them).
  • Minor copy tweaks (e.g., possessive fix in label description).
• Public content mirror in www/apps/book/public/llms-full.txt:
  • Sync the above additions: rank property, ranking section, sorting rules, nested ranking examples, and copy fixes.

^{Written by Cursor Bugbot for commit 1d127af. This will update automatically on new commits. Configure here.}

[changeset-bot]

⚠️ No Changeset found

Latest commit: 1d127af

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

This PR includes no changesets

When changesets are added to this PR, you'll see the packages that this PR includes changesets for and the associated semver types

Click here to learn what changesets are, and how to add one.

Click here if you're a maintainer who wants to add a changeset to this PR

[vercel]

@bqst is attempting to deploy a commit to the medusajs Team on Vercel.

A member of the Team first needs to authorize it.

[shahednasser]

Thank you for your contribution! Added comments for changes.

Once you're done making changes, can you also run these commands in the www/apps/book directory:

yarn lint:content
yarn prep

And commit the file changes

[shahednasser]

Small fixes remaining

[shahednasser]

LGTM thanks!