chore: Reusable pub-sub store util

[pan-kot]

Description

Related links, issue #, if available: n/a

How has this been tested?

Review checklist

The following items are to be evaluated by the author(s) and the reviewer(s).

Correctness

• Changes include appropriate documentation updates.
• Changes are backward-compatible if not indicated, see CONTRIBUTING.md.
• Changes do not include unsupported browser features, see CONTRIBUTING.md.
• Changes were manually tested for accessibility, see accessibility guidelines.

Security

• If the code handles URLs: all URLs are validated through the checkSafeUrl function.

Testing

• Changes are covered with new/existing unit tests?
• Changes are covered with new/existing integration tests?

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 96.34%. Comparing base (c59e8fd) to head (e0a8138).
⚠️ Report is 650 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff            @@
##             main    #3055    +/-   ##
========================================
  Coverage   96.34%   96.34%            
========================================
  Files         780      780            
  Lines       21921    21924     +3     
  Branches     7097     7512   +415     
========================================
+ Hits        21119    21123     +4     
+ Misses        795      749    -46     
- Partials        7       52    +45     

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[pan-kot]

Closed in favour of cloudscape-design/component-toolkit#145