Add a workflow to update the rush shrinkwrap file

[nev21]

No description provided.

[Copilot]

Pull request overview

This PR adds a new GitHub Actions workflow to automatically update the Rush shrinkwrap file when pull requests are opened or updated. The workflow runs rush update --full and commits any changes to the npm-shrinkwrap.json file back to the PR branch.

• Adds automated shrinkwrap updates on PR events and manual dispatch
• Configures Node.js environment and installs Rush globally
• Detects changes to the shrinkwrap file and commits them automatically

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 100.00%. Comparing base (b502b98) to head (0514b91).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##              main      #272   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           26        26           
  Lines          458       458           
  Branches       113       113           
=========================================
  Hits           458       458           

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