sanitize doesn't work well with nested objects in intersections

[troyvgw]

Source code in question: https://github.com/yortus/rtti/blob/main/src/operations/sanitize.ts#L30-L40

This current implementation works for simple intersections of objects, but not nested objects. It basically removes all properties of nested objects except those defined in the last member of the intersection.

To rectify this, it should do a 'deep' intersection of nested properties first, and then delegate to object sanitisation.