fix(mp): T40 UI 设计系统合规审计修复 — 60 页面全覆盖

- 新增 $white 语义变量 + --tk-font-display Token
- 44 处 #fff → $white，2 处 background: #fff → $card
- 14 处 border-radius 硬编码统一为 $r-xs/$r-lg/$r
- 3 处 TSX inline 颜色提取为 SCSS 类（exchange/orders/action-inbox）
- ErrorBoundary 重构：6 个 inline style → SCSS 类 + Design Token
- 2 处离调色板颜色修正（#0284C7→$tx2, #94A3B8→$tx3）
- 2 处静默 catch 块添加状态清理（article/health）
- 趋势页补 Loading/EmptyState；咨询页 GuestGuard 统一
- 4 处 #FFFFFF → $white（mixins/index/exchange/variables）

apps/miniprogram/src/pages/pkg-health/daily-monitoring/index.scss

@@ -245,7 +245,7 @@
 }
 
 .dm-field-warning-low {
-  color: #0284C7;
+  color: $tx2;
 }
 
 /* ── submit ── */

apps/miniprogram/src/pages/pkg-health/trend/index.tsx

@@ -3,6 +3,8 @@ import { View, Text } from '@tarojs/components';
 import { useRouter } from '@tarojs/taro';
 import { useHealthStore } from '@/stores/health';
 import TrendChart from '@/components/TrendChart';
+import Loading from '@/components/Loading';
+import EmptyState from '@/components/EmptyState';
 import { useElderClass } from '../../../hooks/useElderClass';
 import './index.scss';
 
@@ -28,10 +30,15 @@ export default function Trend() {
   const indicator = router.params.indicator || 'heart_rate';
   const [range, setRange] = useState('7d');
   const [points, setPoints] = useState<{ date: string; value: number }[]>([]);
+  const [loading, setLoading] = useState(true);
   const { getTrend } = useHealthStore();
 
   useEffect(() => {
-    getTrend(indicator, range).then(setPoints);
+    setLoading(true);
+    getTrend(indicator, range)
+      .then(setPoints)
+      .catch(() => setPoints([]))
+      .finally(() => setLoading(false));
   }, [indicator, range]);
 
   const meta = INDICATOR_META[indicator] || { label: indicator, unit: '' };
@@ -68,17 +75,27 @@ export default function Trend() {
       </View>
 
       {/* ECharts 折线图 */}
-      <View className='trend-chart-card'>
-        <TrendChart
-          data={points}
-          referenceMin={meta.refMin}
-          referenceMax={meta.refMax}
-          unit={meta.unit}
-        />
-      </View>
+      {loading ? (
+        <View className='trend-chart-card'>
+          <Loading />
+        </View>
+      ) : points.length === 0 ? (
+        <View className='trend-chart-card'>
+          <EmptyState text='暂无趋势数据' />
+        </View>
+      ) : (
+        <View className='trend-chart-card'>
+          <TrendChart
+            data={points}
+            referenceMin={meta.refMin}
+            referenceMax={meta.refMax}
+            unit={meta.unit}
+          />
+        </View>
+      )}
 
       {/* 参考区间 */}
-      {meta.refMin !== undefined && meta.refMax !== undefined && (
+      {!loading && points.length > 0 && meta.refMin !== undefined && meta.refMax !== undefined && (
         <View className='trend-ref-card'>
           <Text className='trend-ref-label'>参考区间</Text>
           <Text className='trend-ref-value'>