feat(campaigns): add portable campaign transfers

src/govoplan_campaign/backend/router.py

@@ -12,12 +12,14 @@ from govoplan_campaign.backend.routes.operations import router as operations_rou
 from govoplan_campaign.backend.routes.reports import router as reports_router
 from govoplan_campaign.backend.routes.schedules import router as schedules_router
 from govoplan_campaign.backend.routes.sharing import router as sharing_router
+from govoplan_campaign.backend.routes.transfers import router as transfers_router
 from govoplan_campaign.backend.routes.versions import router as versions_router
 
 
 router = APIRouter()
 for workflow_router in (
     operations_router,
+    transfers_router,
     campaigns_router,
     assignments_router,
     collaboration_router,