There’s one image from Billie Eilish – Hit Me Hard and Soft: The Tour (Live in 3D) that goes a long way towards defining the concert movie’s entire soul: The 10-time Grammy-winning star double-fisting a microphone and a handheld 3D camera. Bouncing across the stage, she points the lens at herself with glee before flipping it back around at her audience. It’s her music, her performance, her movie, her face on the screen. She is in complete control. It genuinely seems that, to borrow a phrase, she’s happier than ever. Eilish directed Hit Me Hard and Soft in collaboration with James Cameron , who brought his decades of experience in revolutionizing 3D filmmaking to the challenge of the concert film. Filming took place across four nights of Eilish’s Manchester stop on the “Hit Me Hard And Soft” tour (hence, you know, the title) — on hand were 17 cameras, most of which were doing their best to keep up with Eilish as she ran across the stage.…