refactor(v-header): 优化首页案例展示逻辑

- 在获取推荐列表后，限制展示的案例数量为前四个
- 调整案例列表项的宽度为24%，以适应页面布局

src/views/components/v-header/index.vue

@@ -139,7 +139,7 @@
       async infoPages() {
         this.queryParams.type = 5
         let res = await Api.getColumnInfoList(this.queryParams)
-        this.case_list = res.data.list.filter(item => item.recommend == 1)
+        this.case_list = res.data.list.filter(item => item.recommend == 1).slice(0,4)
       },
       hoverItem(val) {
         this.activeIndex = val
@@ -347,7 +347,7 @@
         scrollbar-width: none;
 
         .list-item-i {
-          width: 300px;
+          width: 24%;
           height: fit-content;
           height: 250px;