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Question type: Redshift / Cosmology Entry: TPR, PER, Relaxation Evolution, and the Cosmic Readout. Canonical lane: start at V01-1.15 (The Mechanism of Redshift: TPR Provides the Baseline Color, and PER the Fine Correction). Bridge if needed: V06-6.13, V09-9.6. Default retrieval profile: explain_profile. Forbidden shortcut: Do not begin from mainstream expansion-only language when the user is asking EFT redshift mechanics.