feat(vscode-ide-companion): 增加代码编辑功能和文件操作支持

- 实现了与 Claude Code 类似的代码编辑功能
- 添加了文件打开、保存等操作的支持
- 优化了消息显示，增加了代码高亮和文件路径点击功能
- 改进了用户界面，增加了编辑模式切换和思考模式功能

packages/vscode-ide-companion/src/webview/components/toolcalls/shared/LayoutComponents.tsx

@@ -107,55 +107,3 @@ export const LocationsList: React.FC<LocationsListProps> = ({ locations }) => (
     ))}
   </>
 );
-
-/**
- * Props for DiffDisplay
- */
-interface DiffDisplayProps {
-  path?: string;
-  oldText?: string | null;
-  newText?: string;
-}
-
-/**
- * Display diff with before/after sections
- */
-export const DiffDisplay: React.FC<DiffDisplayProps> = ({
-  path,
-  oldText,
-  newText,
-}) => (
-  <div>
-    <div>
-      <strong>{path || 'Unknown file'}</strong>
-    </div>
-    {oldText !== undefined && (
-      <div>
-        <div
-          style={{
-            opacity: 0.5,
-            fontSize: '0.85em',
-            marginTop: '4px',
-          }}
-        >
-          Before:
-        </div>
-        <pre className="code-block">{oldText || '(empty)'}</pre>
-      </div>
-    )}
-    {newText !== undefined && (
-      <div>
-        <div
-          style={{
-            opacity: 0.5,
-            fontSize: '0.85em',
-            marginTop: '4px',
-          }}
-        >
-          After:
-        </div>
-        <pre className="code-block">{newText}</pre>
-      </div>
-    )}
-  </div>
-);