feat: 优化部分问题，完善选区功能

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

@@ -11,7 +11,7 @@ import LayersList from "./LayersList.vue"; // 引入 LayersList 组件
 //   GroupLayersCommand,
 //   UngroupLayersCommand,
 // } from "../../commands/LayerCommands";
-import { generateId } from "../../utils/helper";
+import { findObjectById, generateId } from "../../utils/helper";
 
 const props = defineProps({
   // layers: Array,
@@ -26,6 +26,7 @@ const props = defineProps({
 
 const emit = defineEmits([
   "add-layer",
+  "add-top-layer",
   "add-group-layer",
   "set-active-layer",
   "toggle-layer-visibility",
@@ -92,6 +93,13 @@ const selectedLayers = computed(() => {
   );
 });
 
+// 计算属性：获取当前是否激活子图层
+const isChildLayerActive = computed(() => {
+  const { parent } = findLayerRecursively(layers.value, props.activeLayerId);
+  if (parent) return true; // 如果有父图层，则表示是子图层
+  return false; // 否则是根图层
+});
+
 // 计算属性：检查是否有选中的图层可以分组
 const canGroupLayers = computed(() => {
   // 直接基于 selectedLayerIds 和 sortableRootLayers 计算，确保响应式
@@ -142,6 +150,9 @@ const canToggleLock = computed(() => {
 function addLayer() {
   emit("add-layer");
 }
+function addTopLayer() {
+  emit("add-top-layer");
+}
 
 function addGroupLayer() {
   emit("add-group-layer");
@@ -590,6 +601,7 @@ function handleLayerClick(layer, event) {
       ) {
         // 如果是组图层，设置第一个子图层为活动图层
         setActiveLayer(layer.children[0].id, { parentId: layer.id });
+        layerManager?.setAllActiveGroupLayerCanvasObject?.(layer);
       } else {
         // 否则直接设置当前图层为活动图层
         setActiveLayer(layer.id);
@@ -1252,6 +1264,14 @@ const forwardEvent = (eventName, ...args) => {
 
         <!-- 常规操作按钮 -->
         <div v-else class="normal-actions">
+          <div
+            v-if="isChildLayerActive"
+            class="add-layer-btn action-btn"
+            @click="addTopLayer"
+            :title="$t('添加顶级图层')"
+          >
+            <SvgIcon name="CPlusTop" size="16"></SvgIcon>
+          </div>
           <div
             class="add-layer-btn action-btn"
             @click="addLayer"