Real-time MediaPipe streaming trackers on live webcam video — one 4-mode block: Hands (21-point skeleton + handedness), Pose (33-point skeleton + person count), Face (478-point mesh + top-8 expression blendshapes behind a default-on toggle), and Gestures (recognized category with a human-readable label). Live FPS; exactly one tracker/WASM task runs at a time. Ships a justified block-local hot-path canvas util (draw-landmarks.ts — single consumer, imports only @localmode/core topology constants under the blocks carve-out). Fully on-device. Split from ui/blocks/vision-lab (Track tab).