fix(MyFamily): 修改图片显示模式为aspectFill

 <!--
  * @Date: 2022-09-19 14:11:06
  * @LastEditors: hookehuyr hookehuyr@gmail.com
- * @LastEditTime: 2025-09-08 18:33:48
+ * @LastEditTime: 2025-09-11 20:23:23
  * @FilePath: /lls_program/src/pages/MyFamily/index.vue
  * @Description: 我的家庭页面 - 展示用户加入的家庭列表
 -->
@@ -36,7 +36,7 @@
           <image
             :src="family.avatar_url || defaultFamilyCoverSvg"
             class="w-full h-44 object-cover"
-            mode="widthFix"
+            mode="aspectFill"
           />
 
           <!-- 家庭名称和大家长信息覆盖层 -->