Homeassitant card editor gui for subcards

[LDprg]

Is your feature request related to a problem? Please describe.
When adding the card you lose all of the gui from all subcards, which is quite frustrating. Especially when working with complicated cards that heavily rely on gui usage or you are a user that heavily relies on the gui.

Describe the solution you'd like
That this cards just like a for example a vertical stack card passes the gui through.

[nima-1102]

+1