- Create build-release.yml workflow to replace .travis.yml
- Build PHP 8.2 with required extensions
- Run PHPUnit tests with MariaDB container
- Build and push Docker images to Docker Hub
- Create/update unstable release on master push
- Add documentation for required secrets
Differences from Travis:
- Uses concurrency groups to cancel in-progress runs
- Separates build and release into distinct jobs
- Uses GitHub's native release action
- No separate SQL Docker image (can be added if needed)
Required secrets: DOCKER_USERNAME, DOCKER_PASSWORD
