A 42-year-old Indian man with a 10-year history of chronic hemolytic anemia presents with severe bone pain and jaundice. On examination, he has hepatosplenomegaly, frontal bossing, and a cardiac murmur. Laboratory findings show: Hemoglobin 8.5 g/dL, reticulocyte count 18%, indirect bilirubin 3.2 mg/dL, LDH 520 U/L, haptoglobin 8 mg/dL. Peripheral blood smear shows spherocytes and polychromasia. Osmotic fragility test is abnormal (lysis at 0.36% NaCl). Genetic testing reveals a mutation in the ANK1 gene. What is the most likely diagnosis?