Add background activity policy and host power monitoring

- Track client leases, host power, and background work eligibility
- Route provider snapshot refreshes through shared background policy
- Add tests for the new policy and related server settings wiring

Co-authored-by: codex <codex@users.noreply.github.com>
d7f9ef7243Julius Marminge committed on 7/29/2026, 11:56:38 AMparent3137c2b
34 files changedLine totals unavailable