Add a Mac (16:10, 2880x1800) platform to the screenshot studio: a
MacBook .usdz model, native-app capture path in capture.sh (no simulator),
and all four marketing layouts. Fix the screen texturing so the capture
fills the display exactly — plain [0,1] planar UVs with a thin black matte
baked into the shot for the rounded-corner margin (replacing the UV
overscan that smeared the edge). Add a horizontal encryption-flow mode
(beams/stream) for the side-by-side laptops in stay-private.
