Alphonse Mucha’s (1860-1939) world feels like a dream in perpetual bloom: maidens in draping robes linger in a golden glow, their coiling hair crowned with halos of flowers and looping vines. It’s the kind of sensual image where a single glance is enough to identify its maker. That instant recognizability propelled the Czech artist to stardom in 1894, when his poster for “Gismonda,” a play starring iconic stage actor Sarah Bernhardt, captured Paris’ attention. His romantic style, featuring what came to be known as the “Mucha woman,” soon spread far beyond the theater, reproduced across furniture, packaging and advertisements for high-end brands. But even as he became synonymous with Art Nouveau, Mucha altered the course of his career at the turn of the century, devoting the rest of his life to championing Czechoslovakia’s independence from the Austro-Hungarian Empire. That shift culminated in “The Slav Epic,” a tour de force that took 18 years to complete. These two facets of the artist — the decorative and the devotional — come into sharp focus in “Alphonse Mu