A 20-year-old male presents with fatigue and poor appetite for 1 month, oliguria, edema, and hypertension (HTN) for 1 week. Lab findings show anemia, hematuria, proteinuria, normal complement C3, elevated serum creatinine and blood urea nitrogen (BUN), and bilateral enlarged kidneys on ultrasound. Clinical diagnosis is acute kidney injury (AKI). If both anti-glomerular basement membrane (GBM) antibody and antineutrophil cytoplasmic antibody (ANCA) are negative, which of the following is the most likely diagnosis?