Add Traveling Salesman Problem (TSP) Algorithms and Tests

[ngtduc693]

Summary

This PR adds a new module for solving the Traveling Salesman Problem (TSP) in C#. It includes two approaches:

- Brute-force search: Finds the optimal route by checking all possible permutations. Suitable for small numbers of cities.
- Nearest neighbor heuristic: Builds a route by always visiting the nearest unvisited city next. Fast but may not be optimal.

AND,

• All code is written using modern C# 10+ syntax and best practices.
• Comments are detailed and clear for educational purposes.

Details

Implements TravelingSalesmanSolver with detailed XML comments explaining the algorithms and usage.
Provides comprehensive unit tests covering all edge cases, invalid inputs, and correctness for both methods.
Updates the README to include TSP in the list of supported problems, with a description and links to the code.

Usage

The brute-force method guarantees the shortest route for small city counts.
The nearest neighbor method is efficient for larger problems and provides a reasonable approximation.

UT evidence

• I have performed a self-review of my code
• My code follows the style guidelines of this project
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Comments in areas I changed are up to date
• I have added comments to hard-to-understand areas of my code
• I have made corresponding changes to the README.md

[codecov]

Codecov Report

❌ Patch coverage is 98.38710% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 96.66%. Comparing base (ed242f4) to head (a89eed3).
⚠️ Report is 1 commits behind head on master.

Files with missing lines	Patch %	Lines
...blems/TravelingSalesman/TravelingSalesmanSolver.cs	98.83%	0 Missing and 1 partial ⚠️
...rithms/RecommenderSystem/CollaborativeFiltering.cs	97.36%	0 Missing and 1 partial ⚠️

Additional details and impacted files

@@ Coverage Diff @@ ## master #536 +/- ## ======================================= Coverage 96.65% 96.66% ======================================= Files 278 279 +1 Lines 10927 11015 +88 Branches 1552 1568 +16 ======================================= + Hits 10562 10648 +86  Misses 232 232 - Partials 133 135 +2 

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[siriak]

Please resolve conflicts

[Copilot]

Pull Request Overview

This PR adds comprehensive support for solving the Traveling Salesman Problem (TSP) in C#, implementing both brute-force and nearest neighbor algorithms with extensive test coverage.

• Implements TravelingSalesmanSolver with brute-force (optimal for small datasets) and nearest neighbor heuristic (fast approximation) methods
• Adds comprehensive unit tests covering edge cases, error handling, and algorithm correctness
• Updates documentation to include TSP in the supported algorithms list

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
README.md	Added TSP to the list of supported algorithms with links to implementation
Algorithms/RecommenderSystem/CollaborativeFiltering.cs	Modernized namespace syntax from braced to file-scoped
Algorithms/Problems/TravelingSalesman/TravelingSalesmanSolver.cs	New TSP solver implementation with brute-force and nearest neighbor algorithms
Algorithms.Tests/RecommenderSystem/CollaborativeFilteringTests.cs	Added additional test cases for edge scenarios and error handling
Algorithms.Tests/Problems/TravelingSalesman/TravelingSalesmanSolverTests.cs	Comprehensive test suite for TSP solver covering all methods and edge cases

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[ngtduc693]

Please resolve conflicts

@siriak I'm done, thanks

[siriak]

Thanks!