Neoadjuvant therapy: Becotatug Vedotin is dosed based on the participant's body weight. In this study, the dosing regimen is 2.3 mg/kg, administered via intravenous infusion on Day 1 of each cycle, once every 3 weeks (Q3W), for a total of 3 treatment cycles. The infusion time for Becotatug Vedotin should be no less than 60min, and it is recommended to be controlled within 60 to 90min. Pucotenlimab is administered at a fixed dose of 200 mg per infusion, via intravenous infusion on Day 1 of each cycle, once every 3 weeks (Q3W), for a total of 3 treatment cycles, with an infusion duration of 60min (±15 min). Becotatug Vedotin and Pucotenlimab are administered on the same day, Pucotenlimab is given first, followed by Becotatug Vedotin, with an interval of no less than 30min between the two infusions.