Current MIM3 export of Mappings doesn't include the known Class & Property URIs of the Mapped Items. Also, we should add No Mapping Found to the mapping predicates, because this is important information that can also be asserted to be proposed or final (not just an implicit result of missing a source or target element). ### Problem / goal SSSOM export is missing semantics that could be used to make better mappings. ### What is the expected outcome? Richer mappings. ### Which (groups of) users will actually use this feature? Mapping users.