Include document info when creating page notes via experimental button

[acelaya]

We have discovered that page notes created via the button rendered when enableExperimentalNewNoteButton is true, do not include the document metadata, since the logic is not triggered in the guest document, as it happens with the regular page notes button or annotations and highlights created from the adder.

This PR adds a new RPC message that can be used for the sidebar to request the guest document info on demand, allowing those page notes to properly include the document metadata.

Test steps

1. Go to http://localhost:3000/document/comments-mode
2. Open the browser console, and go to the network tab
3. Create a comment via "Add comment" button
   
4. Inspect the request payload from the POST http://localhost:5000/api/annotations call, and verify it includes all document metadata.
   
5. If you do the same in main branch, the document will be "empty"
   

TODO

• Add tests

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 99.50%. Comparing base (aaeb9a5) to head (ec5eb13).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #7477   +/-   ##
=======================================
  Coverage   99.50%   99.50%           
=======================================
  Files         271      271           
  Lines       11017    11028   +11     
  Branches     2655     2656    +1     
=======================================
+ Hits        10962    10973   +11     
  Misses         55       55           

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.