When guests arrived at the Hotel d’Orrouer, French couturier Hubert de Givenchy’s stately 18th-century mansion here, they rang a polished brass doorbell on the limestone wall. Once the bell was rung — no sound was made — the guardian would open the right side of the monumental evergreen-lacquered double doors and usher in the guests.
The white pea gravel courtyard was raked to such meticulous perfection it was unthinkable to cross…