[CI/CD] Comprehensive CI/CD pipeline with security scanning

[OneByJorah]

CI/CD Pipeline Checklist

• Create comprehensive GitHub Actions workflow ()
• Add linting (ruff, mypy, black)
• Add security scanning (bandit, safety/pip-audit, trivy, gitleaks)
• Add unit/integration tests with pytest
• Add coverage reporting (pytest-cov, codecov)
• Add Docker build and push
• Add Docker image scanning (trivy)
• Add dependabot for dependency updates
• Add release automation
• Add security policy and SECURITY.md