Coven: Named Runtime Grouping

Under one name, the Coven gathers its fires.

A Coven is a named systemd target emitted when two or more compatible Soulstones share a group. Soulstone groups request membership; [concurrency].conflict_domains separately declares finite-resource incompatibility. A Coven is neither conflict nor eviction policy.

One member emits no target. Different groups create no coexistence promise. Members' effective conflict sets must not overlap; an internally conflicting Coven fails closed. The current Rune schema has no alliances setting and rejects that field.

One Rune may participate in more than one formation:

name = "echo"
groups = ["conversation", "studio"]

That still names one service instance. Starting lychd-coven-conversation.target and lychd-coven-studio.target does not create two copies, and common membership does not prove the complete union fits. The compiled conflict graph remains the executable coexistence law.

For later multi-capability placement, follow the capability and resource design. A CapabilitySetRequest@1 may use a Coven as an operator convenience only after Orchestrator expands and validates every member against measured envelopes and placement profiles. Membership grants no resources, routing, lease, or egress authority. Convergence is serialized, while physical effects remain non-atomic and use compensation, restoration, and containment after partial change.

For inspection, activation requests, priority, switching settings, and Reactor outcome recovery, continue to Runtime transitions. The old operation fragments remain here so existing links still find that passage.