Added FindMiddleNode, FindMiddleNodeTest, ListNode, and corresponding…

[MedhaSunkad13]

… JUnit test

• 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 50.00000% with 10 lines in your changes missing coverage. Please review.
✅ Project coverage is 77.81%. Comparing base (3eb521b) to head (c58d925).
⚠️ Report is 54 commits behind head on master.

Files with missing lines	Patch %	Lines
...lgorithms/datastructures/lists/FindMiddleNode.java	37.50%	10 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##             master    #6836      +/-   ##
============================================
+ Coverage     75.80%   77.81%   +2.00%     
- Complexity     5804     6398     +594     
============================================
  Files           705      735      +30     
  Lines         19846    21353    +1507     
  Branches       3851     4184     +333     
============================================
+ Hits          15045    16615    +1570     
+ Misses         4218     4069     -149     
- Partials        583      669      +86     

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[MedhaSunkad13]

Hi maintainers 👋
I’ve implemented the FindMiddleNode algorithm along with its corresponding ListNode class and FindMiddleNodeTest (JUnit test cases).

The code has been compiled and tested locally using Maven, and all tests passed successfully (BUILD SUCCESS).

If there are any improvements or changes required, I’d be happy to make them.

[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.