STA TWT executor checkpoint on ns-3.48 Local acceptance: 45 test cases passed; announced UL probe recorded 38 DATA PSDU starts inside SPs and zero outside. Scope: local agreements on one associated QoS link. Negotiated TWT, complete unannounced AP delivery, MLO/EMLSR execution and full-frame SP containment remain unsupported. An additional MLO regression remains unresolved; see doc/twt/REGRESSION_STATUS.md.