Describe the feature you'd like

Add .Type property to the objects in Stats.Propulsion, it's value being that of the type property in propulsion.json

Also, add .Designable which indicates what can be used in templates.

Describe why do you think it is needed

It's critical info for correlating to weapon modifiers (see #4700), and generally for autonomous AI bots that don't use hard-coded research paths or design templates.