Add DFS with parent-completion constraint for DAG traversal

[StathisVeinoglou]

Description

This PR adds a new GraphTraversal class that implements a modified DFS traversal order for directed graphs, ensuring that a node is only visited if all its parents have already been visited.
This approach is useful in dependency resolution and neural network computation graph execution order.

• 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 77.77778% with 12 lines in your changes missing coverage. Please review.
✅ Project coverage is 75.12%. Comparing base (16345cb) to head (ec54953).

Files with missing lines	Patch %	Lines
...thealgorithms/graph/PredecessorConstrainedDfs.java	77.77%	6 Missing and 6 partials ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##             master    #6467      +/-   ##
============================================
+ Coverage     75.10%   75.12%   +0.02%     
- Complexity     5556     5575      +19     
============================================
  Files           686      687       +1     
  Lines         19264    19318      +54     
  Branches       3719     3732      +13     
============================================
+ Hits          14468    14513      +45     
- Misses         4239     4244       +5     
- Partials        557      561       +4     

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[StathisVeinoglou]

Thanks for all the suggestions! I believe that i implemented the changes.
Please let me know if anything further is needed