FLX-2114: the run digest moved from the recorded golden baseline

Family: plan/replay binding (the 2000 band)

KERNEL-SPEC section 10 records one golden baseline per simulation under <state_dir>/golden/, and fluxsim verify compares this run's runDigest against it. A difference means the same bundle no longer produces the same run -- the engine, a document, or an input moved. fluxsim verify names the component that moved (or says the inputs moved with every component identical). When the move is intended, re-record the baseline with --update-golden --reason "<why>"; the reason is written into the golden record, so a baseline can never be moved silently.

Look it up offline

$ fluxsim explain FLX-2114

Every code is listed in the error index.