- Created DocumentTagViewSet with CRUD and document listing
- Created DocumentTypeViewSet with CRUD and filtering (active/inactive)
- Created CabinetViewSet for virtual document collections with hierarchy
- Added thumbnail endpoint to DocumentViewSet (GET /documents/{id}/thumbnail/?size=medium)
- Registered all new ViewSets in router:
* /api/v1/document-tags/
* /api/v1/document-types/
* /api/v1/cabinets/
- Thumbnail sizes: admin_thumbnail, small, medium, large
- All ViewSets support search and filtering
- Cabinet ViewSet has add_document/remove_document actions
This completes high-priority missing API endpoints for frontend.
igor_nadein
90bc399d05