fix: Web端Socket.IO连接配置修复

- 传输方式从websocket-only改为polling+websocket双传输,增加连接可靠性
- 连接超时从20秒增加到60秒,匹配后端配置
- 重连次数从20次改为Infinity,永不放弃重连
- connect_error不再每次都设置error状态,避免阻断Socket.IO内置重连
- disconnect事件区分断开原因,transport error时保持connecting状态等待自动重连
- 新建连接前先断开旧socket,防止连接泄漏
- ConnectDialog默认地址从ws://改为http://,符合Socket.IO v4规范
- URL验证器兼容http/https/ws/wss四种协议
- connectToServer自动将ws://转换为http://,向后兼容旧地址

src/components/Connection/ConnectDialog.tsx

@@ -21,20 +21,19 @@ const ConnectDialog: React.FC<ConnectDialogProps> = ({
   const [loading, setLoading] = useState(false)
   const { status: connectionStatus, serverUrl } = useSelector((state: RootState) => state.connection)
 
-  // 预设服务器地址选项
+  // Preset server addresses
   const presetServers = [
-    'ws://localhost:3001',
-    'ws://127.0.0.1:3001',
-    'ws://192.168.1.100:3001', // 示例局域网地址
+    'http://localhost:3001',
+    'http://127.0.0.1:3001',
+    'http://192.168.1.100:3001',
   ]
 
   useEffect(() => {
     if (visible) {
-      // 如果已有服务器地址，使用它作为默认值
       if (serverUrl) {
         form.setFieldValue('serverUrl', serverUrl)
       } else {
-        form.setFieldValue('serverUrl', 'ws://localhost:3001')
+        form.setFieldValue('serverUrl', 'http://localhost:3001')
       }
     }
   }, [visible, serverUrl, form])
@@ -61,20 +60,23 @@ const ConnectDialog: React.FC<ConnectDialogProps> = ({
     form.setFieldValue('serverUrl', url)
   }
 
-  const validateWebSocketUrl = (_: any, value: string) => {
+  const validateServerUrl = (_: any, value: string) => {
     if (!value) {
       return Promise.reject(new Error('请输入服务器地址'))
     }
     
-    if (!value.startsWith('ws://') && !value.startsWith('wss://')) {
-      return Promise.reject(new Error('地址必须以 ws:// 或 wss:// 开头'))
+    if (!value.startsWith('http://') && !value.startsWith('https://') &&
+        !value.startsWith('ws://') && !value.startsWith('wss://')) {
+      return Promise.reject(new Error('地址必须以 http:// 或 https:// 开头'))
     }
     
     try {
-      new URL(value)
+      // Normalize ws:// -> http:// for URL validation
+      const normalized = value.replace(/^ws:\/\//, 'http://').replace(/^wss:\/\//, 'https://')
+      new URL(normalized)
       return Promise.resolve()
     } catch {
-      return Promise.reject(new Error('请输入有效的WebSocket地址'))
+      return Promise.reject(new Error('请输入有效的服务器地址'))
     }
   }
 
@@ -103,19 +105,19 @@ const ConnectDialog: React.FC<ConnectDialogProps> = ({
         form={form}
         layout="vertical"
         initialValues={{
-          serverUrl: 'ws://localhost:3001'
+          serverUrl: 'http://localhost:3001'
         }}
       >
         <Form.Item
           label="服务器地址"
           name="serverUrl"
           rules={[
-            { validator: validateWebSocketUrl }
+            { validator: validateServerUrl }
           ]}
-          help="输入WebSocket服务器地址，例如: ws://localhost:3001"
+          help="输入服务器地址，例如: http://localhost:3001"
         >
           <Input 
-            placeholder="ws://localhost:3001"
+            placeholder="http://localhost:3001"
             size="large"
             autoFocus
             onPressEnter={handleConnect}