fix(cli): hide scrollbars when in alternate buffer copy mode (#18354)

Co-authored-by: Jacob Richman <jacob314@gmail.com>

packages/cli/src/ui/components/shared/VirtualizedList.tsx

@@ -17,6 +17,7 @@ import {
 import type React from 'react';
 import { theme } from '../../semantic-colors.js';
 import { useBatchedScroll } from '../../hooks/useBatchedScroll.js';
+import { useUIState } from '../../contexts/UIStateContext.js';
 
 import { type DOMElement, measureElement, Box } from 'ink';
 
@@ -78,6 +79,7 @@ function VirtualizedList<T>(
     initialScrollIndex,
     initialScrollOffsetInIndex,
   } = props;
+  const { copyModeEnabled } = useUIState();
   const dataRef = useRef(data);
   useEffect(() => {
     dataRef.current = data;
@@ -474,16 +476,21 @@ function VirtualizedList<T>(
   return (
     <Box
       ref={containerRef}
-      overflowY="scroll"
+      overflowY={copyModeEnabled ? 'hidden' : 'scroll'}
       overflowX="hidden"
-      scrollTop={scrollTop}
+      scrollTop={copyModeEnabled ? 0 : scrollTop}
       scrollbarThumbColor={props.scrollbarThumbColor ?? theme.text.secondary}
       width="100%"
       height="100%"
       flexDirection="column"
-      paddingRight={1}
+      paddingRight={copyModeEnabled ? 0 : 1}
     >
-      <Box flexShrink={0} width="100%" flexDirection="column">
+      <Box
+        flexShrink={0}
+        width="100%"
+        flexDirection="column"
+        marginTop={copyModeEnabled ? -scrollTop : 0}
+      >
         <Box height={topSpacerHeight} flexShrink={0} />
         {renderedItems}
         <Box height={bottomSpacerHeight} flexShrink={0} />