SDK-only custom project tool

Tracked by pm-cbwg and pm-w89s.

This package is the end-to-end acceptance proof for pm's universal-tool goal. It is a standalone domain CLI, not an extension: its implementation imports only @unbrained/pm-cli/sdk and composes customization, lifecycle, query, context, annotation, linked-resource, relationship, and governance primitives.

Run the acceptance suite, including the executable adapter contract, against fresh temporary workspaces:

node scripts/run-tests.mjs test -- tests/unit/sdk/sdk-universal-tool-exemplar.spec.ts

The pm-custom flow registers a Deliverable type and reviewing status, creates a related parent/child graph, records comments/notes/learnings, links workspace evidence, reads list/search/context/dependency projections, closes the work with resolution evidence, and returns health/history verification as structured JSON. It never imports src/core, src/cli, or spawns pm.

Use src/index.ts as the copyable library pattern and src/cli.ts as the process-independent executable adapter. The package maps pm-custom to src/entry.ts, which wires that adapter to Node.js arguments, author identity, output streams, and exit status.