Release v0.4.0: Docker Containerization & Deployment

FlowCheck v0.4.0 adds comprehensive Docker support for easy deployment.

- Production-ready Dockerfile with multi-stage builds
- Slim variant (~120MB) for constrained environments
- Development image with testing tools
- Docker Compose stacks (production + dev)
- GitHub Actions CI/CD pipeline
- 5 comprehensive deployment guides

- Docker single container
- Docker Compose (local dev + production)
- Kubernetes with manifests
- CI/CD integration (GitHub Actions, GitLab CI, Jenkins)

- 136 unit tests passing
- Comprehensive security scanning
- Semantic search with TF-IDF
- Non-root container security
- Health checks and graceful shutdown

- docs/deployment/ - 5 deployment guides
- docs/ops/v0.4/ - Implementation reports and audit

See docs/deployment/README.md for quick start.

Release v0.1.0: Production-grade safety layer with Guardian, Semantic…

…, Intent, and Observability layers