enrich is a batch-group member; its individual unit must also be mutually
exclusive with the supervisor. Unit auto-renders via init.py glob of
deploy/decnet-*.service.j2 — no installer list change needed.
Hosts reconcile/enrich/orchestrate/mutate in one process via the
supervision primitive: one import floor, one shared repo/DB pool instead
of 4. Static group registry (membership is architectural, not a knob);
factories lazy-import only the hosted workers. systemd unit Conflicts=
the individual units it replaces and documents the union-of-privileges
cost. Worker code unchanged — any member is extractable by editing _build_specs.
