Zero-shot cross-country transfer: meta-features beat the v3.3 prior on the tail

v3.3 regresses on 16 MENA + former-Soviet countries with <5 labels (OM, UZ, TN, LY, YE, JO, MA…) because no parametric model can learn from so few samples. A meta-feature regressor (regime + geography + historical evidence, evaluated under LOOCV) achieves R² 0.487 and beats v3.3's flat prior on 10/16 tail countries (median +16pp improvement). Live at /v1/forecast/zero-shot/{cc}.