Add the CI workflow

[mourisl]

No description provided.

[Copilot]

Pull request overview

This PR adds a GitHub Actions CI workflow to build HISAT2 on Ubuntu (g++/clang++) and macOS (clang++) and run a minimal smoke test (./hisat2 -h) to validate the produced binary.

Changes:

• Introduces a new workflow CI triggered on pushes and PRs to master.
• Adds an Ubuntu job that builds with a compiler matrix (g++/clang++) and runs a smoke test.
• Adds a macOS job that builds with clang++ and runs the same smoke test.

Suppressed comments (1)

.github/workflows/c-cpp.yml:36

• Same as the Ubuntu job: steps: list items need to be indented under steps, and run: must be a string (inline or block scalar). As written, this section is not valid for GitHub Actions.

    steps:
    - uses: actions/checkout@v4
    - name: build-hisat2
      run:
        make -j$(sysctl -n hw.ncpu) CXX=${{ matrix.compiler }} 

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[mourisl]

It seems this pass the github running. So the indention is not an issue.