A 28-year-old woman from Mumbai presents with a 6-month history of pruritic eczematous lesions on her hands, wrists, and forearms. She works as a healthcare worker and frequently washes her hands with antiseptic soap. On examination, she has erythema, scaling, and fissuring, with sparing of the dorsal web spaces. Her lesions worsen after hand washing and improve with topical emollients. Serum IgE is mildly elevated at 180 IU/mL. Patch testing is planned. What is the most likely diagnosis?