DM-53844: v30 release notes

[timj]

Checklist

• ran Jenkins
• added a release note for user-visible changes to doc/changes

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 84.91%. Comparing base (237ccda) to head (fa41c39).
⚠️ Report is 3 commits behind head on main.
✅ All tests successful. No failed tests found.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #136   +/-   ##
=======================================
  Coverage   84.91%   84.91%           
=======================================
  Files          36       36           
  Lines        7127     7127           
  Branches      874      874           
=======================================
  Hits         6052     6052           
  Misses        821      821           
  Partials      254      254           

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