Utility bind ports with initialization commands
```toml
[plumbing."127.0.0.1:12345"] target = "127.0.0.1:80"
[plumbing."127.0.0.1:23456"] target = "127.0.0.1:2048" resource.setup = { command = "http-server", args = ["-h", "127.0.0.1", "-p", "2048", "-v"] } resource.warmup_millis = 500 ```