A 4D Representation for Training-Free Agentic Reasoning from Monocular Laparoscopic Video. - Maximilian Fehrentz; Nicolas Stellwag; Robert Wiebe; Nicole Thorisch; Fabian Grob; Patrick Remerscheid; Ken-Joel Simmoteit; Benjamin D. Killeen; Christian Heiliger; Nassir Navab (CoRR, 2026)