The capture tool's stdout is block-buffered, so waiting for its directory name
left every image on disk until the capture ended (3,554 PNGs in a 20 s run on
the Frame). Detect the new capture directory instead, decode in three worker
processes, and stop the capture if more than 900 images wait. On the Frame a
30 s run now peaks at 7 images on disk.
Part of #27
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Adds 'pulse', which captures the IR eye cameras through SteamVR's own
eyetracking --calib mode, reduces each image to patch averages and deletes it
immediately, then estimates pulse from skin brightness. Adds heart-check.py to
show OSC readings live and compare recordings with an Apple Health export or
CSV, and a synthetic Mac BLE strap for relay tests.
Part of #27
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
