High above the grand boutique windows of number 24 rue Faubourg Saint-Honoré, where Charles-Émile Hermès relocated his father’s harness workshop in 1880 and first began to retail saddlery, there is an exquisite little-known paradise that overlooks the rooftops of Paris. I stumbled upon some insider photographs by Quentin Bertoux of this secret little Parisian terrace, so let’s take a…