A 58-year-old man from rural India presents with progressive dysphagia and epigastric pain for 4 months. Upper endoscopy reveals a large ulcerating mass in the gastric antrum with biopsy-confirmed adenocarcinoma. CT staging shows locally advanced disease (T3N2M0). He is deemed fit for neoadjuvant chemotherapy followed by gastrectomy. What is the preferred chemotherapy regimen for locally advanced gastric cancer?