Add Strain Hospice for graceful low-win strain retirement.

Archive failed epidemiology strains to museum hospice with SQLite persistence, operator/AI/court triggers, breeding and graft guards, topology museum nodes, and Seer plus oath ledger accountability.

server/internal/api/graft_ws.go

@@ -115,6 +115,15 @@ func (h *WSHub) ApproveFleetGraft(sourceID, targetID string) (strategy.GraftPoli
 	if joinLane == "" {
 		return strategy.GraftPolicy{}, fmt.Errorf("source agent has no tier-success join_lane")
 	}
+	sourceStrain := strategy.NormalizeStrainID(source.SpreadStrain)
+	if sourceStrain == "" {
+		sourceStrain = strategy.StrainFromSpreadLane(joinLane)
+	}
+	if inHospice, err := h.db.IsStrainInHospice(sourceStrain); err != nil {
+		return strategy.GraftPolicy{}, err
+	} else if inHospice {
+		return strategy.GraftPolicy{}, fmt.Errorf("source strain is in hospice (museum archive)")
+	}
 	hr := h.AgentMiningHashrate(targetID)
 	if hr <= 0 {
 		hr = target.MiningHashrate