Compare median post-error intra-command IATs against baseline
(commands not immediately following an errored command):
* ratio ≥ STRESS_EUSTRESS_RATIO_MIN (1.20) → eustress_positive
* ratio ≤ 1/STRESS_DISTRESS_RATIO_MIN → distress_negative
* otherwise → none
Confidence hard-capped at 0.5; 0.30 below
STRESS_MIN_ERRORED_WITH_IATS (2).
high_agitated when any of:
* caps_run_max ≥ 5
* bang_run_max ≥ 3
* fastest typing burst median IAT < 0.06s with ≥ 30 IATs total
low_calm when slowest qualifying burst median IAT > 0.30s with ≥ 30
IATs. Else medium_engaged. Confidence hard-capped at 0.5; 0.30 below
AROUSAL_MIN_IATS.
