fix(scene): drop the first-frame precompile; record round 4 test evidence

src/scene/world/environment.ts

@@ -514,10 +514,6 @@ export async function createProceduralSceneGeneration(
       if (introProgress === null) {
         introProgress =
           snapshot.activeSectionId === 'start' && snapshot.scrollY < 40 ? 0 : 1;
-        // The crane opens on the sky, so the road, car and roadside would
-        // otherwise compile their shaders mid-drive when they first enter the
-        // frame. Compile every visible object now, as the chase framing would.
-        if (introProgress === 0) renderer.compile(scene, camera);
       }
       if (introProgress < 1) {
         // The shot belongs to a visitor who waits at the top. Scrolling,