qector-dem-pipeline

Detector error model (DEM) parsing, collapse, priors, and routing for QECTOR. Covers the manual 14 collapse rule (independent-XOR combination p = p1(1-p2) + p2(1-p1)), per-mechanism prior recalibration, the graphlike/hyperedge boundary, and the worked example p1=0.01, p2=0.02 -> p=0.0296, weight=ln(0.9704/0.0296)=3.489. Load for any DEM-related work: parsing .stim DEMs, building decoders from a DEM, weight…