Add the ability to merge properties into entity definitions

[zoe-codez]

🪤 Context

Need a spot on the UI to provide properties that will be merged with entity attributes.

Entities may not always have the desired attributes available when the type-writer code scans them. This would provide some type definitions that could be merged in with the entity to provide a more consistent picture of what is a valid type for it

📬 Caveats

🩻 Additional details