Adds the skills:admin router (cloud/sdk/skill_api.py) for cloud-skill CRUD
and per-host entitlement grant/revoke with CSRF/scope/audit, and a
host-scoped router serving incremental per-host sync deltas plus the
agent local-skill inventory report/readback. Both composed into the
Cloud API app. cloud-api suite green (46 passed).
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
