fix(performance): refactoring inefficient duplication checking nested for loops

[stefanblaginov]

Refactoring inefficient duplicate-checking nested for loops. The refactoring methodology follows @mttrbrts's (#582) in replacing the nested for loops with ES6's Set structures.

Inefficiency discovery methodology: inspecting all loops in codebase.

Author Checklist

• Ensure you provide a DCO sign-off for your commits using the --signoff option of git commit.
• Vital features and changes captured in unit and/or integration tests
• Commits messages follow AP format
• Extend the documentation, if necessary
• Merging to main from fork:branchname