v1.0.0 - Release for pySigma 1.0.0 Support!

Summary:
Upgrade pySigma-backend-secops to v1.0.0 with pySigma 1.0.0 compatibility and Python modernization.

Changes:

Bump version to 1.0.0 with pySigma ^1.0.0 dependency
Drop Python 3.9, add Python 3.13 support (now ^3.10)
Modernize type hints (Optional[X] → X | None, Dict → dict, etc.)
Replace black with ruff for linting/formatting
Expand test coverage
Update CI workflows for new Python versions