fix: Nearest Greater and Smaller Element Algorithm (Fixes #6656)

[sgindeed]

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[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 75.87%. Comparing base (3eb521b) to head (52c4f7a).

Additional details and impacted files

@@             Coverage Diff              @@
##             master    #6693      +/-   ##
============================================
+ Coverage     75.80%   75.87%   +0.06%     
- Complexity     5804     5828      +24     
============================================
  Files           705      706       +1     
  Lines         19846    19890      +44     
  Branches       3851     3863      +12     
============================================
+ Hits          15045    15091      +46     
+ Misses         4218     4217       -1     
+ Partials        583      582       -1     

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[DenizAltunkapan]

Thank you for your contribution! @sgindeed
However, similar functionality already exists in the following classes:

• NextGreaterElement.java
• NextSmallerElement.java

Your proposed implementation overlaps with these existing ones, so we cannot accept another separate class of the same type.

If you’d like, you can instead improve or refactor the existing classes — for example, by adding clearer documentation, optimizing the logic, or unifying the pattern across “greater” and “smaller” variants.

Thank you again for your effort and understanding! 🙏