GNM-Craniofacial-Approximation-Pipeline: Blender add-on and offline fitting pipeline

A Blender marker add-on and an offline, auditable fitting pipeline for supervised craniofacial approximation research. The pipeline fits a neutral GNM Head identity model to operator-defined skin targets derived from a scanned skull using Umeyama alignment, ridge regression with IRLS, and TPS correction. It features parallel dual viewports and explicit bone-versus-skin distance metrics designed for publication-grade reconstruction.