A 35-year-old woman of Gujarati descent is found to have mild microcytic anemia (Hb 10.5 g/dL, MCV 68 fL) on routine screening. She is asymptomatic with no hepatosplenomegaly. Her 8-year-old daughter has beta-thalassemia major on transfusion therapy. Peripheral blood smear shows target cells and mild anisopoikilocytosis. Hemoglobin electrophoresis reveals: HbA 92%, HbA₂ 4.2%, HbF 1.5%. Serum ferritin is normal. What is the most likely diagnosis?