HOW GRATIFYING it is to see a gift you’ve given someone put to good use. When it comes to coffee-table tomes that you might give the amateur decorator on your list, a book that illuminates as well as beautifully illustrates stands a good chance of becoming the recipient’s dog-eared guide. Accordingly, we’ve sifted through the scores of 2019’s interior design books to find the five gems that most adroitly combine brains and beauty..