PREREG_P: explicit pectoralis major and dual-plane release in a standing gravity-chain finite-element model of small-breast augmentation (preregistration)

Preregistration of the formal batch of a computational (finite-element) study, STEP P: explicit pectoralis major and dual-plane release in a standing gravity-chain model of small-breast augmentation. Signed on 2026-10-06, before any formal run. Full text in Chinese with a one-page English summary in Section 14. SHA-256 of the uploaded file: 4ff54553a45fe454e5b3267cd5d7944390cdd5af868adbf26e977cb529ca6d5c. Preregistration of the preceding study (STEP M): 10.5281/zenodo.23048323.