2026.5.1

fix: refine ViewSet types in SCIP output for Django REST Framework

When indexing Django projects with DRF ViewSets, the SCIP output contained
generic base class symbols (BaseSerializer, Model) instead of the concrete
types defined on the ViewSet. This made call_hierarchy and find_usages
return unhelpful generic references.

Add a post-processing pass (viewsetTypeRefinement) that detects ModelViewSet
subclasses in the SCIP document and substitutes base class symbols with the
concrete types found on serializer_class and queryset fields. Also fix
lookUpClassMember to skip Any/Unknown members in the MRO so mixins resolve
correctly.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>