A 4-month-old male presents with clusters of brief flexion spasms of the trunk and limbs occurring predominantly upon waking, with developmental regression over 2 weeks. His mother reports capturing video of the episodes. EEG shows the pattern marked **D** in the diagram — hypsarrhythmia with a modified variant showing focal lateralization and increased posterior synchrony. Examination reveals ash-leaf macules on the trunk under Wood lamp. Which of the following represents the most evidence-based first-line management approach for this condition?