Photo: Courtesy of Adam Lippes Had the robber barons been boutique shoppers, they might have found themselves right at home in a crop of new stores with especially ornate interiors — where the walls are wood-paneled, the display cases are claw-footed, and the couches are heavily throw-pillowed — that have opened around the city. Buttresses decorated with stone lions’ heads mark the exterior of French crystal-glassware-maker Lalique ’s (21 E. 63rd St.) latest store, called Maison d’Artiste,