Add the island configuration forms

christian.wiedemann → made their first commit to this issue’s fork.

This is also the opportunity to add getSummary() on island forms

Added the show variants/grouped/mosaic option
Added validation for no show or no provider
Added no_ui support
Add a basic form test (not covering the configuration, just the config entity)
Add some generics from 📌 Provide some generic components Active

Some styles fixes, phrasing and sorting.

Automatically closed - issue fixed for 2 weeks with no activity.