feat(奖励页面): 在奖励标题前添加商家名称并注释有效期规则显示

在奖励卡片和详情页中，将商家名称添加到奖励标题前以提高信息清晰度
同时注释掉详情页中有效期规则的显示，因业务需求暂时不需要展示

@@ -39,7 +39,7 @@
                     </view>
 
                     <!-- Expiration Rules -->
-                    <view v-if="reward.expiration_rules && reward.expiration_rules.length > 0">
+                    <!-- <view v-if="reward.expiration_rules && reward.expiration_rules.length > 0">
                         <h2 class="text-lg font-medium mb-3">有效期</h2>
                         <view class="space-y-2 text-gray-600">
                             <view v-for="rule in reward.expiration_rules" :key="rule" class="flex text-sm">
@@ -47,7 +47,7 @@
                                 <p>{{ rule }}</p>
                             </view>
                         </view>
-                    </view>
+                    </view> -->
 
                     <!-- Expire Time -->
                     <view v-if="reward.expire_time">

@@ -33,7 +33,7 @@
         >
           <image :src="reward.thumbnail || 'https://placehold.co/120x120/e2f3ff/0369a1?text=券&font=roboto'" class="w-16 h-16 rounded-lg mr-4 flex-shrink-0" mode="aspectFill" />
           <view class="flex-1 min-w-0">
-            <view class="font-medium text-base mb-1">{{ reward.title }}</view>
+            <view class="font-medium text-base mb-1">{{ reward.merchant_name }}·{{ reward.title }}</view>
             <view v-if="reward.status === 'UNUSED'" class="text-xs text-gray-400">
               有效期至：{{ formatDate(reward.expire_time) }}
             </view>