As a cinematic study in risk and reward, the first four features from director Damien Chazelle just plain work, often dazzlingly. He knows how and when to move a camera. You know how rare that is these days? Steven Spielberg; Paul Thomas Anderson; a few others. And Chazelle. His spare and lovely Harvard thesis project, “Guy and Madeline on a Park Bench,” led to the outlandishly intense music-school melodrama “Whiplash.” That begot the massive popular success of “La La Land,” a swell variation on themes laid out in “Guy and Madeline.” Then came the intriguing Neil Armstrong biopic “First Man,” …