the ring reads out over ipc as turn decisions (V-564)

Same shape as TickTrace and RecentEvents: a bounded daemon ring, so the store
adapter refuses rather than pretending a table exists. No voice wiring means an
empty list and not an error, because a box with no voice path has had no turns
to arbitrate.

internal/ipc/unimplemented.go

@@ -144,6 +144,9 @@ func (UnimplementedCoreAPI) RevertFact(ctx context.Context, key string) (int64,
 func (UnimplementedCoreAPI) TickTrace(ctx context.Context) (TickTrace, error) {
 	return TickTrace{}, ErrNotImplemented
 }
+func (UnimplementedCoreAPI) TurnDecisions(ctx context.Context, n int) ([]TurnDecision, error) {
+	return nil, ErrNotImplemented
+}
 func (UnimplementedCoreAPI) MorningStatus(ctx context.Context) ([]MorningRoutineStatus, error) {
 	return nil, ErrNotImplemented
 }