v1.18.0

• Added a self-contained MCP Apps review surface for render_preview and render_preview_batch, with image/overlay
  navigation, structured issue severity, notes, accepted variants, run-scoped async state, host theming, and fullscreen
  support.
• Added manifest-bound artifact:// PNG reads with bounded no-follow regular-file access, PNG decoding, and path, size,
  and SHA-256 verification; the app has an empty network CSP and keeps local source paths out of visible review state.
• Added a reproducible Node 24 frontend build, a self-containment verifier that enforces wheel/sdist payload parity, and
  CI/release guards for packaged output.
• Added a bounded loopback harness and recorded generated-fixture machine proof against the official MCP Apps
  basic-host without counting it as real beta or adoption evidence.
• Hardened MCP Registry verification for slow public reads while preserving metadata and latest-version checks.