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>

packages/builtin-tools/src/tools/FileEditTool/UI.tsx

@@ -1,5 +1,7 @@
 import type { ToolResultBlockParam } from '@anthropic-ai/sdk/resources/index.mjs';
+import type { StructuredPatchHunk } from 'diff';
 import * as React from 'react';
+import { Suspense, use, useState } from 'react';
 import { FileEditToolUseRejectedMessage } from 'src/components/FileEditToolUseRejectedMessage.js';
 import { MessageResponse } from 'src/components/MessageResponse.js';
 import { extractTag } from 'src/utils/messages.js';
@@ -10,10 +12,15 @@ import { Text } from '@anthropic/ink';
 import { FilePathLink } from 'src/components/FilePathLink.js';
 import type { Tools } from 'src/Tool.js';
 import type { Message, ProgressMessage } from 'src/types/message.js';
+import { adjustHunkLineNumbers, CONTEXT_LINES } from 'src/utils/diff.js';
 import { FILE_NOT_FOUND_CWD_NOTE, getDisplayPath } from 'src/utils/file.js';
+import { logError } from 'src/utils/log.js';
 import { getPlansDirectory } from 'src/utils/plans.js';
+import { readEditContext } from 'src/utils/readEditContext.js';
+import { firstLineOf } from 'src/utils/stringUtils.js';
 import type { ThemeName } from 'src/utils/theme.js';
 import type { FileEditOutput } from './types.js';
+import { findActualString, getPatchForEdit, preserveQuoteStyle } from './utils.js';
 
 export function userFacingName(
   input:
@@ -84,6 +91,8 @@ export function renderToolResultMessage(
     <FileEditToolUpdatedMessage
       filePath={filePath}
       structuredPatch={structuredPatch}
+      firstLine={originalFile.split('\n')[0] ?? null}
+      fileContent={originalFile}
       style={style}
       verbose={verbose}
       previewHint={isPlanFile ? '/plan to preview' : undefined}
@@ -99,7 +108,7 @@ export function renderToolUseRejectedMessage(
     replace_all?: boolean;
     edits?: unknown[];
   },
-  _options: {
+  options: {
     columns: number;
     messages: Message[];
     progressMessagesForMessage: ProgressMessage[];
@@ -109,14 +118,40 @@ export function renderToolUseRejectedMessage(
     verbose: boolean;
   },
 ): React.ReactElement {
-  const { style, verbose } = _options;
+  const { style, verbose } = options;
   const filePath = input.file_path;
-  const isNewFile = input.old_string === '';
+  const oldString = input.old_string ?? '';
+  const newString = input.new_string ?? '';
+  const replaceAll = input.replace_all ?? false;
+
+  // Defensive: if input has an unexpected shape, show a simple rejection message
+  if ('edits' in input && input.edits != null) {
+    return (
+      <FileEditToolUseRejectedMessage file_path={filePath} operation="update" firstLine={null} verbose={verbose} />
+    );
+  }
+
+  const isNewFile = oldString === '';
+
+  // For new file creation, show content preview instead of diff
+  if (isNewFile) {
+    return (
+      <FileEditToolUseRejectedMessage
+        file_path={filePath}
+        operation="write"
+        content={newString}
+        firstLine={firstLineOf(newString)}
+        verbose={verbose}
+      />
+    );
+  }
 
   return (
-    <FileEditToolUseRejectedMessage
-      file_path={filePath}
-      operation={isNewFile ? 'write' : 'update'}
+    <EditRejectionDiff
+      filePath={filePath}
+      oldString={oldString}
+      newString={newString}
+      replaceAll={replaceAll}
       style={style}
       verbose={verbose}
     />
@@ -149,3 +184,103 @@ export function renderToolUseErrorMessage(
   }
   return <FallbackToolUseErrorMessage result={result} verbose={verbose} />;
 }
+
+type RejectionDiffData = {
+  patch: StructuredPatchHunk[];
+  firstLine: string | null;
+  fileContent: string | undefined;
+};
+
+function EditRejectionDiff({
+  filePath,
+  oldString,
+  newString,
+  replaceAll,
+  style,
+  verbose,
+}: {
+  filePath: string;
+  oldString: string;
+  newString: string;
+  replaceAll: boolean;
+  style?: 'condensed';
+  verbose: boolean;
+}): React.ReactNode {
+  const [dataPromise] = useState(() => loadRejectionDiff(filePath, oldString, newString, replaceAll));
+  return (
+    <Suspense
+      fallback={
+        <FileEditToolUseRejectedMessage file_path={filePath} operation="update" firstLine={null} verbose={verbose} />
+      }
+    >
+      <EditRejectionBody promise={dataPromise} filePath={filePath} style={style} verbose={verbose} />
+    </Suspense>
+  );
+}
+
+function EditRejectionBody({
+  promise,
+  filePath,
+  style,
+  verbose,
+}: {
+  promise: Promise<RejectionDiffData>;
+  filePath: string;
+  style?: 'condensed';
+  verbose: boolean;
+}): React.ReactNode {
+  const { patch, firstLine, fileContent } = use(promise);
+  return (
+    <FileEditToolUseRejectedMessage
+      file_path={filePath}
+      operation="update"
+      patch={patch}
+      firstLine={firstLine}
+      fileContent={fileContent}
+      style={style}
+      verbose={verbose}
+    />
+  );
+}
+
+async function loadRejectionDiff(
+  filePath: string,
+  oldString: string,
+  newString: string,
+  replaceAll: boolean,
+): Promise<RejectionDiffData> {
+  try {
+    // Chunked read — context window around the first occurrence. replaceAll
+    // still shows matches *within* the window via getPatchForEdit; we accept
+    // losing the all-occurrences view to keep the read bounded.
+    const ctx = await readEditContext(filePath, oldString, CONTEXT_LINES);
+    if (ctx === null || ctx.truncated || ctx.content === '') {
+      // ENOENT / not found / truncated — diff just the tool inputs.
+      const { patch } = getPatchForEdit({
+        filePath,
+        fileContents: oldString,
+        oldString,
+        newString,
+      });
+      return { patch, firstLine: null, fileContent: undefined };
+    }
+    const actualOld = findActualString(ctx.content, oldString) || oldString;
+    const actualNew = preserveQuoteStyle(oldString, actualOld, newString);
+    const { patch } = getPatchForEdit({
+      filePath,
+      fileContents: ctx.content,
+      oldString: actualOld,
+      newString: actualNew,
+      replaceAll,
+    });
+    return {
+      patch: adjustHunkLineNumbers(patch, ctx.lineOffset - 1),
+      firstLine: ctx.lineOffset === 1 ? firstLineOf(ctx.content) : null,
+      fileContent: ctx.content,
+    };
+  } catch (e) {
+    // User may have manually applied the change while the diff was shown.
+    logError(e as Error);
+    return { patch: [], firstLine: null, fileContent: undefined };
+  }
+}