Seam Craft — render prerequisites for scene-to-scene transitions This is the render-correctness doctrine for PLV scene-to-scene seams: the prerequisites and master-timeline mechanics that make any transition composite correctly, independent of which specific transition is chosen. The per-transition catalog (crossfade, push-slide, zoom-through, cut-the-curve, …) lives in the transition registry — this page is the doctrine that sits underneath all of them. The transitions this doctrine governs are Tier-B-ready : pure transform / opacity / filter on the two scene clip wrappers ( ), no injected o…