A 62-year-old woman from Mumbai with a 6-month history of progressive dyspnea, orthopnea, and lower-limb edema presents to the hospital. She reports a 2-month prodrome of fever, arthralgias, and weight loss. On examination, blood pressure is 148/92 mmHg, JVP is elevated, and she has a palpable nodule over the right ulnar nerve. Laboratory findings: ESR 95 mm/h, CRP 18 mg/dL, hemoglobin 9.2 g/dL, serum creatinine 2.1 mg/dL, and urinalysis shows proteinuria (3.5 g/24 h) with dysmorphic RBCs. Serum hepatitis B surface antigen is positive. Echocardiography reveals a dilated right ventricle with moderate tricuspid regurgitation. What is the most likely diagnosis?