Corrects the tests that were failing due to the model changes
Adds a new test case to replicate the scenario in the bug (implicit from_entities)
Corrects journey calculation to properly work with implicit from_entities (the last node in the current path can lead to the current via if the anatomical entity is explicit in the from_entities or if the from_entities is implicit and the via order is the next in sequence - bold was missing from the algorithm)
Misc:
Replaces placeholder frontend code in the origins widget with the correct name
closes https://metacell.atlassian.net/browse/SCKAN-284
Misc: