open ui-group dialog by config env variable

### Description

I know that I can use a ui-group type as config environment variable in a subflow. It would be good to use this env variable again in the
{"groups":{"show":["group_name:widget_name"]}} to open a dialog. So no hardcoded names are needed in the subflow.

### Have you provided an initial effort estimate for this issue?

I am no FlowFuse team member