throughyear 0.1.0

• Initial release.
• Latent multivariate-normal linking of interims to the summative scale with measurement error and missing interims (ty_link()).
• Two-stage MST simulation with cold-start and prior-informed routing (ty_mst(), ty_administer(), ty_policies()).
• Fairness diagnostics by group (ty_fairness()).
• Decision accuracy and consistency of through-year scores versus a single summative (ty_decisions()).