public ApplicationInstance toApplicationInstance(ApplicationInfo applicationInfo,
                                                     ServiceStatusProvider serviceStatusProvider) {
        var generator = new ApplicationInstanceGenerator(applicationInfo, zone);
        return generator.makeApplicationInstance(serviceStatusProvider);
    }
Create service model based primarily on super model.

If the configServerhosts is non-empty, a config server application is added.
service-monitor/src/main/java/com/yahoo/vespa/service/model/ModelGenerator.java