TimeLesSeg: Unified Contrast-Agnostic Cross-Sectional and Longitudinal MS Lesion Segmentation via a Stochastic Generative Model. - Vicent Caselles Costa; Eloy Martínez-Heras; Giuseppe Pontillo; Zoe Mendelsohn; Elena M. Marrón; Juan Luis García Fernández; Laia Subirats; Jon Stutters; Jeremy Chataway; Frederik Barkhof; Sara Llufriu; Ferran Prados (CoRR, 2026)