Workstream B phase 1 (node-side consume). The signed app-catalog can now carry a
full manifest per entry; the orchestrator overlays it over the disk manifest
(origin-wins) with disk as the migration fallback. Moves apps toward
registry-distributed manifests with no OTA-shipped disk file.
- app_catalog: `manifest: Option<Value>` on AppCatalogEntry (forward-compatible,
covered by the existing release-root signature over the raw JSON);
`catalog_manifest_values()` accessor.
- prod_orchestrator: `load_manifests` overlays catalog manifests after the disk
walk; `catalog_manifest_to_overlay()` returns None (→ disk fallback) on
unparseable value / app-id mismatch / failed validate() / build source
(build contexts aren't registry-distributed yet — phase 1 is image-only).
- manifest_dir stays PathBuf (build-only field); image-only apps never read it.
- 6 unit tests; compiles clean. No-op until a catalog embeds a manifest, so
existing nodes are unaffected.
See docs/registry-manifest-design.md.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>