BU79 Residual Stratification and Task-Completion Boundary under B_U From Same-Layer Alignment and Higher-Order Retained Chains to Application-Level Standing

This paper develops BU79|Residual Stratification and Task-Completion Boundary under B_U as a general application-layer interface within the B_U sequence. Its central claim is that practical alignment cannot be treated as a universal demand for total residual elimination. In real tasks, engineering systems, research procedures, organizational cooperation, human interaction, and social operations, alignment first requires a clearly defined task-completion boundary. Only after the object, action, constraint, verification, cost, residual tolerance, time window, and human-confirmation gates are specified can a result obtain application-level standing. The paper begins from the residual stratification rule:…