While reading Victoria Sweet’s fascinating new book, “God’s Hotel”, I felt compelled to Google “Laguna Honda.” That’s the name of the charity hospital--what the French call an “Hôtel Dieu”--at the center of Sweet’s narrative. Surely Sweet invented this place: A hospital where patients lie in rows of beds on open wards, sometimes for months? A hospital with its own greenhouse, barnyard, and aviary? It sounded more likely to have existed in medieval Europe than in 21st century San Francisco.