Observer World Section Structure: Causal Consistency, Conditionalization, and Boundary Time Geometry

Within the unified time scale and boundary time geometry framework, we provide an axiomatizable characterization of ``what world observers see.'' Starting point: given global boundary algebra and quantum state, all ``world sections'' satisfying field equations and causality form a geometric--measure space; concrete observers access only subfamilies compatible with their worldline, resolution, and records, while ``superposition'' is not simultaneous multiple realization of experiential world but