work together. Regardless of 'environment', workloads can talk with each other and obey the Istio configuration resources, but each environment can use different Istio versions and different configuration defaults. `istioctl kube-inject` or the automatic sidecar injector are used to select the environment. In the case of the sidecar injector, the namespace label `istio-env: <NAME_OF_ENV>` is used instead of the conventional `istio-injected: true`. The name of the environment is defined as the namespace...