eslint was red at HEAD (5b715ac) in files untouched by this branch: unused statSync/dirname (check-plugin-api.mjs), unused PrefsSchema (src/index.ts, tests/smoke.spec.ts) and two Function types (tests/smoke.spec.ts). No behaviour change.
- Copy check-plugin-api.mjs into scripts/ (from WorkBuddy diagnosis) - Add 'verify' script: node scripts/check-plugin-api.mjs - 5-section contract check: dependency versions vs DSH runtime, import symbols vs runtime exports, slot registration, removed/deprecated APIs, inline package dependency closure - All 5 sections pass (4 deprecation warnings, non-blocking)