fix: 修复对话停止和会话记忆保存问题

- apiClient 添加 stopDialog 接口
- dialogService 添加 getSegments/getAccumulatedText 方法
- dialogService.abort 调用后端停止接口
- messageHandler.abortCurrentDialog 保存中止前的对话内容
- userInteraction 添加 getWebviewPanel 方法
- webviewContent 添加 resetSegmentedMessage 命令处理
- 修复停止后新消息覆盖旧消息的问题

src/services/toolExecutor.ts

@@ -313,22 +313,19 @@ async function executeWaveformSummary(args: WaveformSummaryArgs): Promise<string
  * 保存知识图谱到 .iccoder/knowledge.json
  */
 async function executeKnowledgeSave(args: KnowledgeSaveArgs): Promise<string> {
-  const workspaceFolders = vscode.workspace.workspaceFolders;
-  if (!workspaceFolders || workspaceFolders.length === 0) {
+  const workspaceFolder = getWorkspaceFolder();
+  if (!workspaceFolder) {
     throw new Error('请先打开一个工作区');
   }
 
-  const workspacePath = workspaceFolders[0].uri.fsPath;
-  const iccoderDir = path.join(workspacePath, '.iccoder');
-  const knowledgePath = path.join(iccoderDir, 'knowledge.json');
+  const iccoderDirUri = vscode.Uri.joinPath(workspaceFolder.uri, '.iccoder');
+  const knowledgeUri = vscode.Uri.joinPath(iccoderDirUri, 'knowledge.json');
 
-  // 确保 .iccoder 目录存在
-  if (!fs.existsSync(iccoderDir)) {
-    fs.mkdirSync(iccoderDir, { recursive: true });
-  }
+  // 确保 .iccoder 目录存在（兼容远程/虚拟工作区）
+  await vscode.workspace.fs.createDirectory(iccoderDirUri);
 
-  // 写入知识图谱
-  fs.writeFileSync(knowledgePath, args.data, 'utf-8');
+  // 写入知识图谱（UTF-8）
+  await vscode.workspace.fs.writeFile(knowledgeUri, Buffer.from(args.data || '', 'utf-8'));
 
   return `知识图谱已保存: .iccoder/knowledge.json`;
 }
@@ -338,21 +335,36 @@ async function executeKnowledgeSave(args: KnowledgeSaveArgs): Promise<string> {
  * 从 .iccoder/knowledge.json 加载知识图谱
  */
 async function executeKnowledgeLoad(): Promise<string> {
-  const workspaceFolders = vscode.workspace.workspaceFolders;
-  if (!workspaceFolders || workspaceFolders.length === 0) {
+  const workspaceFolder = getWorkspaceFolder();
+  if (!workspaceFolder) {
     throw new Error('请先打开一个工作区');
   }
 
-  const workspacePath = workspaceFolders[0].uri.fsPath;
-  const knowledgePath = path.join(workspacePath, '.iccoder', 'knowledge.json');
+  const knowledgeUri = vscode.Uri.joinPath(workspaceFolder.uri, '.iccoder', 'knowledge.json');
 
-  // 如果文件不存在，返回空图谱
-  if (!fs.existsSync(knowledgePath)) {
-    return JSON.stringify({ directed: true, nodes: [], links: [] });
+  try {
+    const bytes = await vscode.workspace.fs.readFile(knowledgeUri);
+    const content = Buffer.from(bytes).toString('utf-8');
+    return content;
+  } catch (error) {
+    // 文件不存在：返回空图谱
+    if (error instanceof vscode.FileSystemError && error.code === 'FileNotFound') {
+      // 与后端 KnowledgeGraph 结构保持一致（nodes/edges + nodeClass 多态字段）
+      return JSON.stringify({ taskId: '', version: 1, module: null, nodes: [], edges: [] });
+    }
+    throw error;
+  }
+}
+
+function getWorkspaceFolder(): vscode.WorkspaceFolder | undefined {
+  const folders = vscode.workspace.workspaceFolders;
+  if (!folders || folders.length === 0) {
+    return undefined;
   }
 
-  const content = fs.readFileSync(knowledgePath, 'utf-8');
-  return content;
+  const activeUri = vscode.window.activeTextEditor?.document?.uri;
+  const activeFolder = activeUri ? vscode.workspace.getWorkspaceFolder(activeUri) : undefined;
+  return activeFolder ?? folders[0];
 }
 
 /**