fix: Fixed server install scripts

server/cmd/main.go

@@ -19,6 +19,13 @@ func main() {
 	mongoURI := getEnv("MONGO_URI", "mongodb://localhost:27017")
 	dbName := getEnv("MONGO_DB", "vantage")
 
+	// Agents dial gRPC directly, so there is no sane default: falling back to the
+	// public web host would hand every new agent a config pointing at a port that
+	// does not speak gRPC. Fail loudly at boot instead of at install time.
+	if os.Getenv("GRPC_HOST") == "" {
+		log.Fatal("GRPC_HOST is required (host:port agents dial for gRPC)")
+	}
+
 	if err := db.Connect(mongoURI, dbName); err != nil {
 		log.Fatalf("failed to connect to MongoDB: %v", err)
 	}