Feature add runnable service

[lukasmittag]

That something like velocitas exec runtime-local runservice <service-id> is doable. We do not want to start the service at during runtime up because we maybe not need it then. Second one would be to have a interactive client come up in a separate terminal.

In the runtime.json you would then specify:

 {
                "key": "runnable",
                "value": "true"
            },

[lukasmittag]

will not be merged not intended solution