Phase 8: Information Per Token metrics New metrics: - MDL contribution (leave-one-out compression, bytes/token) - Corpus cross-entropy surprisal (bigram, bits/token) - IDF density (mean IDF/token) - Composite information score (normalized 0-1) Also includes: - Instruction type extraction refactored to analysis package - XML wrapper tag similarity inflation fix - Contradiction detector threshold calibration (polarity 0.6, scope 0.7)