refactor(mp): 统一空状态为 EmptyState 组件 + 清理旧 Tab CSS

- 4 个页面的内联空状态替换为共享 EmptyState 组件
  (messages / action-inbox / pkg-health/alerts / mall)
- 清理 10 个页面的旧 Tab CSS（迁移到 SegmentTabs 后不再需要）
- 清理 elder-mode 中已删除的 mall-empty-state 引用

apps/miniprogram/src/pages/mall/index.scss

@@ -207,58 +207,3 @@
   }
 }
 
-/* ─── 空状态 ─── */
-.mall-empty-state {
-  display: flex;
-  flex-direction: column;
-  align-items: center;
-  justify-content: center;
-  padding: 100px 40px;
-}
-
-.empty-icon {
-  width: 120px;
-  height: 120px;
-  border-radius: 50%;
-  background: $pri-l;
-  @include flex-center;
-  margin-bottom: 32px;
-}
-
-.empty-char {
-  font-family: 'Georgia', 'Times New Roman', serif;
-  font-size: var(--tk-font-hero);
-  font-weight: bold;
-  color: $pri;
-  line-height: 1;
-}
-
-.empty-title {
-  font-size: var(--tk-font-body-lg);
-  font-weight: 600;
-  color: $tx;
-  margin-bottom: 12px;
-}
-
-.empty-hint {
-  font-size: var(--tk-font-h1);
-  color: var(--tk-text-secondary);
-  text-align: center;
-  margin-bottom: 24px;
-}
-
-.empty-action {
-  background: $pri;
-  border-radius: $r;
-  padding: 16px 48px;
-
-  &:active {
-    opacity: 0.85;
-  }
-}
-
-.empty-action-text {
-  font-size: var(--tk-font-body-lg);
-  color: $white;
-  font-weight: 600;
-}

apps/miniprogram/src/pages/mall/index.tsx

@@ -8,6 +8,7 @@ import { useAuthStore } from '../../stores/auth';
 import { usePointsStore } from '../../stores/points';
 import Loading from '../../components/Loading';
 import ErrorState from '../../components/ErrorState';
+import EmptyState from '../../components/EmptyState';
 import { useElderClass } from '../../hooks/useElderClass';
 import './index.scss';
 
@@ -137,16 +138,13 @@ export default function Mall() {
   if (noProfile) {
     return (
       <View className={`mall-page ${modeClass}`}>
-        <View className='mall-empty-state'>
-          <View className='empty-icon'>
-            <Text className='empty-char'>档</Text>
-          </View>
-          <Text className='empty-title'>请先完善个人档案</Text>
-          <Text className='empty-hint'>建档后即可使用积分商城、签到等功能</Text>
-          <View className='empty-action' onClick={() => Taro.navigateTo({ url: '/pages/pkg-profile/family-add/index' })}>
-            <Text className='empty-action-text'>去建档</Text>
-          </View>
-        </View>
+        <EmptyState
+          icon='档'
+          text='请先完善个人档案'
+          hint='建档后即可使用积分商城、签到等功能'
+          actionText='去建档'
+          onAction={() => Taro.navigateTo({ url: '/pages/pkg-profile/family-add/index' })}
+        />
       </View>
     );
   }
@@ -195,13 +193,7 @@ export default function Mall() {
       {error ? (
         <ErrorState onRetry={() => loadAll()} />
       ) : products.length === 0 && !loading ? (
-        <View className='mall-empty-state'>
-          <View className='empty-icon'>
-            <Text className='empty-char'>礼</Text>
-          </View>
-          <Text className='empty-title'>暂无商品</Text>
-          <Text className='empty-hint'>更多好物即将上架</Text>
-        </View>
+        <EmptyState icon='礼' text='暂无商品' hint='更多好物即将上架' />
       ) : (
         <View className='product-grid'>
           {products.map((item) => (