A 28-year-old woman is brought to the trauma bay after a stab wound to the right lower abdomen. She is restless, pale, and diaphoretic. Vital signs: BP 88/56 mmHg, HR 128/min, RR 24/min, SpO₂ 96% on supplemental oxygen. Abdominal examination reveals a single stab wound with minimal external bleeding, rigid abdomen, and severe tenderness. FAST examination shows free fluid in the right paracolic gutter and pelvis. What is the most appropriate immediate management?