The World War I adventure may be light on character, but it’s heavy, and effective, on making the horrors of trench warfare and combat survival look like a series of exciting challenges to be overcome, one gaming level at a time. Last weekend, at the British Academy of Film and Television Arts, “1917” snagged the awards for best film, best director and, deservedly, best cinematography (Roger Deakins, a true master). It also won for best British film, production design, visual effects and sound. So. It remains the front runner.