[oezsoyik] Boost test exercise

[ozsoyisik]

Here is the link to my pull request

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This pull request introduces continuous integration (CI) for the project, improves CMake configuration for dependency linking, and adds a new test suite for matrix file I/O. The most significant changes are the addition of a GitHub Actions CI workflow, enhanced CMake handling for the yaml-cpp dependency, and new automated tests for matrix reading functionality.

• Added a GitHub Actions workflow (.github/workflows/ci.yml) to run style checks (clang-format), build the project, and execute tests automatically on pushes and pull requests.
• Included a CI badge in README.md to display build status.
• Updated CMakeLists.txt to robustly detect and link the correct yaml-cpp target, preventing build errors across different environments.
• Ensured test executable links against the correct yaml-cpp target and added a dedicated test for matrix I/O.
• Added tests/MatrixIOTest.cpp, a Boost-based test suite that verifies matrix file reading, error handling for missing files and incorrect column counts, and tolerance for floating-point parsing differences.