moves Citation and Fulltext database records directly into parent Study records as nested mappings
consolidates CitationScreening and FulltextScreening records into a single collection of Screening records, using study_id and stage fields instead of citation_id/fulltext_id
updates db orm relationships and trigger events accordingly
updates API logic accordingly, without affecting behavior from the perspective of API callers via hacks, alternate schemas, and white lies
refactors db model imports to module-level, for cleaner namespaces and better behavior in case of future db model changes
changes
CitationandFulltextdatabase records directly into parentStudyrecords as nested mappingsCitationScreeningandFulltextScreeningrecords into a single collection ofScreeningrecords, usingstudy_idandstagefields instead ofcitation_id/fulltext_id