feat: 新增 StressMeter 组件，移除原 HRV 压力监测代码

app/(tabs)/statistics.tsx

@@ -3,6 +3,7 @@ import { BMICard } from '@/components/BMICard';
 import { CircularRing } from '@/components/CircularRing';
 import { NutritionRadarCard } from '@/components/NutritionRadarCard';
 import { ProgressBar } from '@/components/ProgressBar';
+import { StressMeter } from '@/components/StressMeter';
 import { WeightHistoryCard } from '@/components/WeightHistoryCard';
 import { Colors } from '@/constants/Colors';
 import { getTabBarBottomPadding } from '@/constants/TabBar';
@@ -210,53 +211,7 @@ export default function ExploreScreen() {
           <WeightHistoryCard />
 
           {/* HRV压力监测卡片 */}
-          <View style={[styles.hrvCard, { backgroundColor: '#F0F7FF' }]}>
-            <View style={styles.hrvHeader}>
-              <View style={styles.hrvIconContainer}>
-                <Ionicons name="heart" size={24} color="#3B82F6" />
-              </View>
-              <Text style={styles.hrvTitle}>压力监测</Text>
-            </View>
-
-            <View style={styles.hrvContent}>
-              <View style={styles.hrvValueContainer}>
-                <Text style={styles.hrvValue}>{hrvValue}</Text>
-                <Text style={styles.hrvUnit}>毫秒</Text>
-              </View>
-
-              <View style={[styles.hrvStatus,
-              hrvStatus === '放松' ? { backgroundColor: '#DCFCE7' } :
-                hrvStatus === '正常' ? { backgroundColor: '#FEF3C7' } :
-                  { backgroundColor: '#FEE2E2' }
-              ]}>
-                <Text style={[styles.hrvStatusText,
-                hrvStatus === '放松' ? { color: '#166534' } :
-                  hrvStatus === '正常' ? { color: '#92400E' } :
-                    { color: '#991B1B' }
-                ]}>{hrvStatus}</Text>
-                <Text style={styles.hrvEmoji}>
-                  {hrvStatus === '放松' ? '😌' :
-                    hrvStatus === '正常' ? '😊' :
-                      '😰'}
-                </Text>
-              </View>
-            </View>
-
-            <View style={styles.hrvSliderContainer}>
-              <View style={styles.hrvSliderTrack}>
-                <View style={[styles.hrvSliderProgress, {
-                  width: `${Math.min(100, Math.max(0, (hrvValue / 150) * 100))}%`,
-                  backgroundColor: hrvStatus === '放松' ? '#10B981' :
-                    hrvStatus === '正常' ? '#F59E0B' : '#EF4444'
-                }]} />
-              </View>
-              <View style={styles.hrvLabels}>
-                <Text style={styles.hrvLabel}>放松</Text>
-                <Text style={styles.hrvLabel}>正常</Text>
-                <Text style={styles.hrvLabel}>紧张</Text>
-              </View>
-            </View>
-          </View>
+          <StressMeter value={hrvValue} status={hrvStatus} />
 
           {/* 查看更多 */}
           <View style={styles.viewMoreContainer}>
@@ -641,99 +596,4 @@ const styles = StyleSheet.create({
     color: '#192126',
     marginLeft: 4,
   },
-  hrvCard: {
-    backgroundColor: '#F0F7FF',
-    borderRadius: 22,
-    padding: 20,
-    marginBottom: 16,
-    shadowColor: '#000',
-    shadowOffset: {
-      width: 0,
-      height: 2,
-    },
-    shadowOpacity: 0.1,
-    shadowRadius: 8,
-    elevation: 5,
-  },
-  hrvHeader: {
-    flexDirection: 'row',
-    alignItems: 'center',
-    marginBottom: 16,
-  },
-  hrvIconContainer: {
-    width: 40,
-    height: 40,
-    borderRadius: 12,
-    backgroundColor: '#DBEAFE',
-    alignItems: 'center',
-    justifyContent: 'center',
-    marginRight: 12,
-  },
-  hrvTitle: {
-    fontSize: 18,
-    fontWeight: '800',
-    color: '#1E293B',
-  },
-  hrvContent: {
-    flexDirection: 'row',
-    alignItems: 'center',
-    justifyContent: 'space-between',
-    marginBottom: 20,
-  },
-  hrvValueContainer: {
-    flexDirection: 'row',
-    alignItems: 'baseline',
-  },
-  hrvValue: {
-    fontSize: 36,
-    fontWeight: '800',
-    color: '#1E293B',
-    marginRight: 4,
-  },
-  hrvUnit: {
-    fontSize: 16,
-    fontWeight: '600',
-    color: '#64748B',
-  },
-  hrvStatus: {
-    flexDirection: 'row',
-    alignItems: 'center',
-    backgroundColor: '#DCFCE7',
-    paddingHorizontal: 12,
-    paddingVertical: 6,
-    borderRadius: 20,
-  },
-  hrvStatusText: {
-    fontSize: 14,
-    fontWeight: '600',
-    color: '#166534',
-    marginRight: 4,
-  },
-  hrvEmoji: {
-    fontSize: 16,
-  },
-  hrvSliderContainer: {
-    marginTop: 8,
-  },
-  hrvSliderTrack: {
-    height: 8,
-    backgroundColor: '#E2E8F0',
-    borderRadius: 4,
-    marginBottom: 8,
-    overflow: 'hidden',
-  },
-  hrvSliderProgress: {
-    height: '100%',
-    backgroundColor: '#3B82F6',
-    borderRadius: 4,
-  },
-  hrvLabels: {
-    flexDirection: 'row',
-    justifyContent: 'space-between',
-  },
-  hrvLabel: {
-    fontSize: 12,
-    fontWeight: '500',
-    color: '#64748B',
-  },
 });