feat: 添加后端服务地址自定义配置功能

- 在设置面板添加后端服务地址配置项
   - 支持保存、加载和重置自定义配置
   - 配置持久化存储，重启后保留
   - 添加 SSE 请求日志用于验证配置

src/panels/ICHelperPanel.ts

@@ -18,6 +18,7 @@ import {
   startChangeSession,
   handleOpenFileDiff,
 } from "../utils/messageHandler";
+import { setCustomConfig } from "../config/settings";
 import { compactDialog } from "../services/apiClient";
 import { VCDViewerPanel } from "./VCDViewerPanel";
 import { ChatHistoryManager } from "../utils/chatHistoryManager";
@@ -684,6 +685,21 @@ export async function showICHelperPanel(
           // 退出登录（前端已有确认对话框）
           vscode.commands.executeCommand("ic-coder.logout");
           break;
+        case "saveGeneralSettings":
+          // 保存通用设置
+          context.globalState.update('generalSettings', message.settings);
+          // 更新运行时配置（包括清空）
+          setCustomConfig({ backendUrl: message.settings.backendUrl || '' });
+          vscode.window.showInformationMessage('设置已保存');
+          break;
+        case "loadGeneralSettings":
+          // 加载通用设置
+          const settings = context.globalState.get('generalSettings');
+          panel.webview.postMessage({
+            command: 'loadedGeneralSettings',
+            settings: settings
+          });
+          break;
       }
     },
     undefined,