fix: 保留用户/规则高级设置并增强节点运行时恢复 (#468)

* fix: 用户编辑时 maxConn 字段未正确回填

- User 接口添加 maxConn 类型定义
- handleEdit 中回填 maxConn 值
- normalizeUserItem 添加 maxConn 字段处理

解决编辑用户时最大连接数显示为 0 的问题

* fix: 保留转发设置并增强节点运行时恢复

go-backend/internal/http/handler/control_plane.go

@@ -1705,6 +1705,12 @@ func buildForwardServiceConfigs(baseName string, forward *forwardRecord, tunnel
 		if cLimiterName != "" {
 			service["climiter"] = cLimiterName
 		}
+		if forward.ProxyProtocol > 0 {
+			if service["metadata"] == nil {
+				service["metadata"] = map[string]interface{}{}
+			}
+			service["metadata"].(map[string]interface{})["proxyProtocol"] = forward.ProxyProtocol
+		}
 		if protocol == "udp" {
 			listenerMetadata := map[string]interface{}{
 				"keepAlive": true,
@@ -1716,7 +1722,10 @@ func buildForwardServiceConfigs(baseName string, forward *forwardRecord, tunnel
 			service["handler"].(map[string]interface{})["chain"] = fmt.Sprintf("chains_%d", forward.TunnelID)
 		}
 		if tunnel != nil && tunnel.Type == 1 && strings.TrimSpace(node.InterfaceName) != "" {
-			service["metadata"] = map[string]interface{}{"interface": node.InterfaceName}
+			if service["metadata"] == nil {
+				service["metadata"] = map[string]interface{}{}
+			}
+			service["metadata"].(map[string]interface{})["interface"] = node.InterfaceName
 		}
 		if limiterID != nil && *limiterID > 0 {
 			service["limiter"] = strconv.FormatInt(*limiterID, 10)