feat(ActivitiesCover): 添加积分规则说明组件

 <!--
  * @Date: 2022-09-19 14:11:06
  * @LastEditors: hookehuyr hookehuyr@gmail.com
- * @LastEditTime: 2025-09-22 15:41:46
+ * @LastEditTime: 2025-09-25 10:41:54
  * @FilePath: /lls_program/src/pages/ActivitiesCover/index.vue
  * @Description: 活动海报页面 - 展示活动信息并处理定位授权
 -->
@@ -25,6 +25,13 @@
 
     <!-- 底部按钮区域 -->
     <view class="bottom-section">
+      <!-- 积分规则说明 -->
+      <view class="bg-blue-50 border border-blue-200 rounded-lg p-4 mb-4 opacity-85">
+        <text class="text-blue-500 text-sm font-medium block mb-2">积分规则说明：</text>
+        <text class="text-blue-500 text-xs leading-relaxed block mb-1" style="padding-left: 20rpx; text-indent: -20rpx;">• 打卡任意1关，视为参与，奖励1000积分</text>
+        <text class="text-blue-500 text-xs leading-relaxed block mb-1" style="padding-left: 20rpx; text-indent: -20rpx;">• 打卡任意7关，视为完成，奖励5000积分</text>
+        <text class="text-blue-500 text-xs leading-relaxed block mb-1" style="padding-left: 20rpx; text-indent: -20rpx;">• 不需要区分打卡点的先后次序</text>
+      </view>
       <!-- 未授权定位提示 - 仅在用户点击参加活动且未授权时显示 -->
       <view v-if="showLocationPrompt && !hasLocationAuth && !locationError" class="location-tip" @click="retryGetLocation">
         <view class="tip-content">