How celebrating personal milestones, and those of others, is good for you and your business — In a recent New Yorker article, highlighting how HGTV is planning on reinventing itself to better appeal to our stay-at-home, DIY-while-you-stream aspirations, Loren Ruch, the network’s executive of development and production, pointed out a significant human insight: “I love doing this, because ninety-five per cent of the people who are…