setup_cell.py no longer creates mail/radicale/webdav config and data dirs —
those are managed by ServiceComposer when services are installed. Added
data/services/ for ServiceComposer. sanity_check.py now uses stdlib urllib
and discovers installed services via /api/services/active before checking
their status routes.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>