Lzcstan/IDEAL-Age: IDEAL-Age v1.2.1: Ablation models update

This release serves as a minor update to v1.2.0, providing supplementary pre-trained models used for the ablation studies presented in our manuscript. Key updates in this release: Added Ablation Models: We have included download links and configuration details for the ablation models in the README.md. Model trained with both regression and classification losses. Model trained with only regression loss. These additions further facilitate the complete reproduction and evaluation of our study. Full Changelog: https://github.com/Lzcstan/IDEAL-Age/compare/1.2.0...1.2.1