deps: Upgrade

```
go: upgraded github.com/spf13/cobra v1.8.1 => v1.9.1
go: upgraded github.com/spf13/pflag v1.0.5 => v1.0.7
```

Make GO 1.23 the lower version

github: Update GitHub actions

deps: Update all direct dependencies

* Running   go get $(go list -f '{{if not (or .Main .Indirect)}}{{.Path}}{{end}}' -m all)
* Also go mod tidy

Fix handling of aliases

See gohugoio/hugo#11090

Fix unknown command error message

Revise the Commander (again)

Improve test coverage for error situations

readme: Add a paragraph about the difference between this and Cobra