- update_node: shallow-merge partial config into a single node without
  rewriting the whole conclave definition. Fetches the current nodes,
  patches one, and PUTs the array back so edges stay intact.
- release-macos.sh: one-command build + codesign + notarize + publish
  for darwin-arm64/x64. Hardened runtime + JIT entitlements (required
  for bun-compiled binaries). Uploads to a GitHub prerelease matching
  existing asset names.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>