Chamber Specification
Invariant: S(H) = path-ensemble entropy reduction (counterfactual structure)
Falsifier: Utility realized before S ≥ S_crit
Expected Signature: Ensemble reorganization then utility (C_u) — delayed onset
Coupling Rule: τ admissible iff S_t ≥ S_crit (no collapse, gated realization)
Utility: Shared EMA threshold (k=8 consecutive steps above U_crit)
Ensemble: K rollouts × L lookahead steps → binary entropy of utility predictability