feat: add --version flag to CLI (fixes #63)

[Dreamstick9]

Description

Implements the requested --version flag for the CLI.

Updated src/pygha/cli.py to include the argument using action="version".

Added a new test case in tests/test_cli.py to verify the correct version string is printed and the system exits with code 0.

Related Issue

Fixes #63

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update

Checklist

• All tests pass locally (pytest)
• I have written or updated tests for any changes
• I have updated the documentation for any changes
• I have updated changelog.md and referred to the issue in the changelog entry

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.

📢 Thoughts on this report? Let us know!

[parneetsingh022]

Hi @Dreamstick9, thanks for your PR, it looks good. Could you please update docs/cli.rst and CHANGELOG.md as well? Once those are updated, I’ll be able to merge your PR.

[github-actions]

Hi @Dreamstick9, this is the PyGHA bot! 🤖

Thanks for your contribution! We will review your changes and get back to you soon.

All standard checks (Tests, Docs, Changelog) look good! ✅

Please make sure you've read our Contributing Guidelines.

By contributing, you agree that your contributions will be licensed under the MIT License.

[parneetsingh022]

@Dreamstick9 Thanks for the PR. All changes looks good, I'm merging the PR.