0.9.0

Added

• Typed ess-build/1, ess-runtime/1, ess-release/1, ess-stack/1,
  ess-stack-lock/1, ess-environment/1, and ess-deployment/1 formats establish the deterministic
  lowering seam from semantic systems to independently released Helm deployments. ESS projects
  BuildKit and chart inputs, verifies immutable executor evidence, and refuses unresolved
  stage-owned obligations; it still never builds, publishes, or applies anything.
• The ess CLI compiles build and runtime IR, verifies releases, resolves stacks from an
  explicit offline catalogue, projects BuildKit and Helm files, compiles environment deployments,
  and reports the exact component releases changed between two deployment documents.