feat(contract): D-MBX-A6 Phase 1 — planner⟷ractor⟷surreal meta-DTO (kanban + soa_view + StepDomain::Kanban)

feat(contract): D-MBX-A6 Phase 1 — planner⟷ractor⟷surreal meta-DTO (kanban + soa_view + StepDomain::Kanban) #548