feat(i18n): 增强生理周期模块的国际化支持，添加多语言格式和翻译

components/menstrual-cycle/Legend.tsx

@@ -1,19 +1,21 @@
 import React from 'react';
+import { useTranslation } from 'react-i18next';
 import { StyleSheet, Text, View } from 'react-native';
 import { STATUS_COLORS } from './constants';
 import { LegendItem } from './types';
 
-const LEGEND_ITEMS: LegendItem[] = [
-  { label: '经期', key: 'period' },
-  { label: '预测经期', key: 'predicted-period' },
-  { label: '排卵期', key: 'fertile' },
-  { label: '排卵日', key: 'ovulation-day' },
-];
-
 export const Legend: React.FC = () => {
+  const { t } = useTranslation();
+  const legendItems: LegendItem[] = [
+    { label: t('menstrual.legend.period'), key: 'period' },
+    { label: t('menstrual.legend.predictedPeriod'), key: 'predicted-period' },
+    { label: t('menstrual.legend.fertile'), key: 'fertile' },
+    { label: t('menstrual.legend.ovulation'), key: 'ovulation-day' },
+  ];
+
   return (
     <View style={styles.legendRow}>
-      {LEGEND_ITEMS.map((item) => (
+      {legendItems.map((item) => (
         <View key={item.key} style={styles.legendItem}>
           <View
             style={[