Setting up a Docker network through GUI or CLI to interconnect my apps

[LarsR]

[Implemented] Inter-app communication in 24.10 Electric Eel

Problem/Justification In TrueNAS SCALE 24.04, it was possible for apps to communicate with each other via cluster.local domain names since they were all on the same network. For example, I use the Nginx Proxy Manager app to reverse proxy to another app on the same TrueNAS machine by using its internal domain name, such as http://immich.ix-immich.svc.cluster.local:30041. In 24.10, this is no longer possible if using the default apps catalog since each app has its own Docker network that is not s…