Use strings.Join instead of += in loop

[tangrufus]

No description provided.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 85.51%. Comparing base (93ac538) to head (ab4b26c).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main      #79      +/-   ##
==========================================
- Coverage   85.56%   85.51%   -0.06%     
==========================================
  Files          10       10              
  Lines         492      490       -2     
==========================================
- Hits          421      419       -2     
  Misses         54       54              
  Partials       17       17              

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[Copilot]

Pull Request Overview

This PR refactors the Or.String() method to improve performance by replacing string concatenation with strings.Join(), reducing time complexity from O(n²) to O(n).

• Replaced manual string concatenation loop with pre-allocated slice and strings.Join
• Added strings package import
• Maintained identical output format with " || " separator

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