Reproducibility package for an observer-split compatibility test of the Roschin-Godin rotating magnetic-system report

This record provides the reproducibility package supporting a short Letter on an observer-split compatibility analysis of the published Roschin-Godin rotating magnetic-system report. The package includes Online Resource 1 with the extended technical derivation, spreadsheet calculator, CSV tables, figure sources and previews, Stan model, and Python scripts used for full Bayesian reproducibility. The package is supporting material only; it is not the journal manuscript itself and should not be cited as a separate competing paper.