Fix/convex hull order

[Kavindya-Kariyawasam]

Implemented Graham's scan algorithm to ensure convex hull points are returned in CCW order. This fixes issues with downstream algorithms like Rotating Calipers that require properly ordered hull vertices.

• I have read CONTRIBUTING.md.
• This pull request is all my own work -- I have not plagiarized it.
• All filenames are in PascalCase.
• All functions and variable names follow Java naming conventions.
• All new algorithms have a URL in their comments that points to Wikipedia or other similar explanations.
• All new code is formatted with clang-format -i --style=file path/to/your/file.java

[codecov-commenter]

Codecov Report

❌ Patch coverage is 83.87097% with 5 lines in your changes missing coverage. Please review.
✅ Project coverage is 75.63%. Comparing base (a0b6c52) to head (844dbf8).

Files with missing lines	Patch %	Lines
...in/java/com/thealgorithms/geometry/ConvexHull.java	83.87%	2 Missing and 3 partials ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##             master    #6623      +/-   ##
============================================
- Coverage     75.74%   75.63%   -0.11%     
  Complexity     5765     5765              
============================================
  Files           701      701              
  Lines         19757    19771      +14     
  Branches       3831     3835       +4     
============================================
- Hits          14964    14954      -10     
- Misses         4214     4235      +21     
- Partials        579      582       +3     

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[DenizAltunkapan]

@Kavindya-Kariyawasam Please fix the failing workflows so I can start the review.

[github-actions]

This pull request has been automatically closed because its workflows or checks failed and it has been inactive for more than 14 days. Please fix the workflows and reopen if you'd like to continue. Merging from main/master alone does not count as activity.