Add Cloud Map seeder discovery with VPC Lattice operator templates.

Agents poll AETHERFORGE_CLOUD_MAP_ENDPOINT to sync know_node gossip; deploy plans attach route_via DNS hints for standalone operator registries.

server/internal/cloudmap/registry_test.go

@@ -1,4 +1,4 @@
-package cloudmap
+package cloudmap
 
 import "testing"
 
@@ -7,3 +7,19 @@ func TestSeederDNSName(t *testing.T) {
 		t.Fatalf("got %q", got)
 	}
 }
+
+func TestKnowNodeTargets(t *testing.T) {
+	doc := RegistryDocument{
+		Namespace: "prod.local",
+		Service:   "seeder",
+		Instances: []RegistryInstance{
+			{AgentID: "a1", Healthy: true},
+			{AgentID: "a2", Healthy: false},
+			{DNSName: "seeder.svc.prod.local", Healthy: true},
+		},
+	}
+	got := KnowNodeTargets(doc)
+	if len(got) != 2 || got[0] != "a1" || got[1] != "seeder.svc.prod.local" {
+		t.Fatalf("got=%v", got)
+	}
+}