BIDS-SRB Preregistration Protocol: Pre-outcome Authority v1.0

Pre-outcome preregistration protocol for the BIDS Semantic Robustness Benchmark (BIDS-SRB). The frozen denominator is N=9. At registration, scientific execution is not authorized, execution-authorized cases are 0, baseline/sham scientific outcomes are 0, and admitted metadata-fault outcomes are 0. The archived authority freezes the response taxonomy, endpoint/statistics rules, truth ceiling, amendment history including canonicalizer v5.2, authority hashes, claim ceilings, and public software provenance before admitted scientific execution.