docs: ADR-081 add AR camera overlay with floating charts + lower third
- AR overlay: live camera feed with skeleton, gesture cursor, and
floating charts anchored to hand/body position
- Lower third: RuView "pi" logo, vital signs, gesture state, sensor
status in broadcast-style bar (semi-transparent dark, teal accents)
- 6 composited layers: camera → skeleton → cursor → chart → labels → lower third
- Chart placement rules: follows dominant hand, stays in frame bounds
- Skeleton style: teal keypoints/bones, yellow highlight on active hand
- Cursor types: open hand, pointing ray, grab, pinch, ghost (CSI-only)
Co-Authored-By: claude-flow <ruv@ruv.net>
68d47a25d5