fix: 恢复消息流中 diff 高亮渲染功能

还原 commit 51b8ad46 删除的 diff highlight 显示：FileEdit/FileWrite 工具
执行成功后重新展示 StructuredDiffList，拒绝时重新展示高亮代码预览或
带上下文的 diff 视图。

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

src/components/FileEditToolUpdatedMessage.tsx

@@ -1,23 +1,31 @@
+import type { StructuredPatchHunk } from 'diff';
 import * as React from 'react';
-import { Text } from '@anthropic/ink';
+import { useTerminalSize } from '../hooks/useTerminalSize.js';
+import { Box, Text } from '@anthropic/ink';
 import { count } from '../utils/array.js';
 import { MessageResponse } from './MessageResponse.js';
+import { StructuredDiffList } from './StructuredDiffList.js';
 
 type Props = {
   filePath: string;
-  structuredPatch: { lines: string[] }[];
+  structuredPatch: StructuredPatchHunk[];
+  firstLine: string | null;
+  fileContent?: string;
   style?: 'condensed';
   verbose: boolean;
   previewHint?: string;
 };
 
 export function FileEditToolUpdatedMessage({
-  filePath: _filePath,
+  filePath,
   structuredPatch,
+  firstLine,
+  fileContent,
   style,
   verbose,
   previewHint,
 }: Props): React.ReactNode {
+  const { columns } = useTerminalSize();
   const numAdditions = structuredPatch.reduce((acc, hunk) => acc + count(hunk.lines, _ => _.startsWith('+')), 0);
   const numRemovals = structuredPatch.reduce((acc, hunk) => acc + count(hunk.lines, _ => _.startsWith('-')), 0);
 
@@ -39,7 +47,7 @@ export function FileEditToolUpdatedMessage({
 
   // Plan files: invert condensed behavior
   // - Regular mode: just show the hint (user can type /plan to see full content)
-  // - Condensed mode (subagent view): show the text
+  // - Condensed mode (subagent view): show the diff
   if (previewHint) {
     if (style !== 'condensed' && !verbose) {
       return (
@@ -52,5 +60,19 @@ export function FileEditToolUpdatedMessage({
     return text;
   }
 
-  return <MessageResponse>{text}</MessageResponse>;
+  return (
+    <MessageResponse>
+      <Box flexDirection="column">
+        <Text>{text}</Text>
+        <StructuredDiffList
+          hunks={structuredPatch}
+          dim={false}
+          width={columns - 12}
+          filePath={filePath}
+          firstLine={firstLine}
+          fileContent={fileContent}
+        />
+      </Box>
+    </MessageResponse>
+  );
 }