Add git tag trigger to GitHub Actions push workflow for PyPI releases

[milliyin]

📝 Problem Description

Currently, pushing Git release tags (e.g. git push origin v0.0.1) does not trigger the GitHub Actions workflow. The top-level on.push configuration in .github/workflows/ci.yml is restricted to branches: [main], omitting tags: ["v*"].

As a result, PyPI trusted publishing is not automatically triggered upon pushing version tags.

💡 Proposed Solution

1. Add tags: ["v*"] under on.push in .github/workflows/ci.yml.
2. Update the build job condition to accept refs/tags/v* so PyPI release builds execute upon tag creation.

✅ Acceptance Criteria

• Pushing a version tag vX.Y.Z triggers the GitHub Actions CI workflow.
• Package build and PyPI publish steps execute automatically upon tag push.