fix(collapsible): remove slot and emit

src/components/VCollapsible/VCollapsibleGroup.vue

@@ -24,7 +24,7 @@ const props = withDefaults(defineProps<Props>(), {
 });
 
 const {accordion, items} = toRefs(props);
-const emit = defineEmits(['update:modelValue', 'update:items', 'item:change']);
+const emit = defineEmits(['update:modelValue', 'update:items', 'item:change', 'onClickItems']);
 const groupItems = ref(items.value);
 
 watch(
@@ -47,19 +47,25 @@ const onChange = (isOpen: boolean, item: CollapsibleItem, idx: number) => {
     });
   }
 };
+const onEventItems = (item: CollapsibleItem, idx: number) => { 
+}
 </script>
 
 <template>
   <div ref="root">
     <slot>
-      <slot name="header">
+      <slot name="group:header" >
       </slot>
       <VCollapsible
         v-for="(item, idx) in groupItems"
         v-model="item.isOpen"
         v-bind="item"
         @change="onChange($event, item, idx)"
       >
+        <template #header >
+          <slot name="item:header"  :item="item" :index="idx">
+          </slot>
+        </template>
         <slot name="items" :row="item" :index="idx">
           <slot :name="`item.${idx}`" :item="item">
             {{ item.content }}