fix: stabilize portfolio scrolling and loading

Remove skeleton swaps and deferred layout estimates, restore reveal state, and use native proximity scrolling for project cards. Also make the Docker build npm registry configurable.

src/components/scenes/AboutRiverScene.tsx

@@ -269,7 +269,7 @@ const createAboutScene: SceneFactory = ({ pointer, theme, reduceMotion }) => {
   };
 };
 
-export function AboutRiverScene({ onReady }: { onReady?: () => void }) {
+export function AboutRiverScene() {
   const { theme } = useTheme();
-  return <ThreeCanvas className={styles.aboutScene} createScene={createAboutScene} theme={theme} onReady={onReady} />;
+  return <ThreeCanvas className={styles.aboutScene} createScene={createAboutScene} theme={theme} />;
 }