fix: 添加液化操作错误提示，优化用户体验,修复液化点击空白区域液化效果被重置的问题

src/component/Canvas/CanvasEditor/components/LiquifyPanel.vue

@@ -138,6 +138,7 @@ import {
 import { OperationType } from "../utils/layerHelper";
 import { LiquifyRealTimeUpdater } from "../managers/liquify/LiquifyRealTimeUpdater";
 import { LiquifyStateManager } from "../managers/liquify/LiquifyStateManager";
+import { Modal } from "ant-design-vue";
 
 // Props定义
 const props = defineProps({
@@ -431,7 +432,19 @@ function showPanel(event) {
   if (!detail.canLiquify && !detail.targetObject) {
     if (detail.layerStatus && detail.layerStatus.message) {
       console.log("液化操作提示:", detail.layerStatus.message);
+      Modal.error({
+        title: "错误提示",
+        content: detail.layerStatus.message,
+        okText: "确定",
+        centered: true,
+      });
     } else {
+      Modal.error({
+        title: "错误提示",
+        content: "未选择有效图像或图层不适合液化操作",
+        okText: "确定",
+        centered: true,
+      });
       console.log("未选择有效图像或图层不适合液化操作");
     }
     visible.value = true; // 仍然显示面板以便用户看到提示
@@ -868,18 +881,18 @@ async function handleMouseDown(event) {
       console.log(
         `开始液化操作，图像坐标: (${imageCoords.x}, ${imageCoords.y})`
       );
+
+      // 应用液化效果
+      applyLiquifyAtPoint(pointer.x, pointer.y);
+
+      // 开始持续按压
+      isPressing.value = true;
+      pressStartTime.value = Date.now();
+      pressX.value = pointer.x;
+      pressY.value = pointer.y;
+      startPressTimer();
     }
   }
-
-  // 应用液化效果
-  applyLiquifyAtPoint(pointer.x, pointer.y);
-
-  // 开始持续按压
-  isPressing.value = true;
-  pressStartTime.value = Date.now();
-  pressX.value = pointer.x;
-  pressY.value = pointer.y;
-  startPressTimer();
 }
 
 /**