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.

agent/deploy/cloud_map_test.go

@@ -0,0 +1,43 @@
+package deploy
+
+import (
+	"os"
+	"strings"
+	"testing"
+)
+
+func TestFetchCloudMapRegistry(t *testing.T) {
+	SetCloudMapHTTPGetForTest(func(url string) ([]byte, error) {
+		return []byte(`{"namespace":"prod.local","service":"seeder","instances":[{"agent_id":"seed-a","dns_name":"seeder.svc.prod.local","healthy":true,"fetch_url":"http://10.0.1.50/manifest"}]}`), nil
+	})
+	defer SetCloudMapHTTPGetForTest(nil)
+	doc, err := FetchCloudMapRegistry("http://registry.local/v1/seeder")
+	if err != nil {
+		t.Fatal(err)
+	}
+	records := CloudMapKnowNodeRecords(doc)
+	if len(records) != 1 || records[0].TargetAgentID != "seed-a" {
+		t.Fatalf("records=%+v", records)
+	}
+}
+
+func TestAppendSpreadRouteTelemetryIncludesRouteVia(t *testing.T) {
+	got := appendSpreadRouteTelemetry("joined", &SpreadRouteHint{EgressAgentID: "egress-1", RouteVia: "seeder.svc.prod.local"})
+	if got == "" || !strings.Contains(got, "route_via=seeder.svc.prod.local") {
+		t.Fatalf("got=%q", got)
+	}
+}
+
+func TestCloudMapEndpointFromEnv(t *testing.T) {
+	t.Setenv(cloudMapEnvEndpoint, "http://127.0.0.1:8080/registry.json")
+	if got := CloudMapEndpoint(); got != "http://127.0.0.1:8080/registry.json" {
+		t.Fatalf("got=%q", got)
+	}
+}
+
+func TestCloudMapEndpointUnset(t *testing.T) {
+	_ = os.Unsetenv(cloudMapEnvEndpoint)
+	if got := CloudMapEndpoint(); got != "" {
+		t.Fatalf("got=%q", got)
+	}
+}