修复日历跨年不显示纪念日

原 buildEventIndex / loadMonthEvents 用 a.solarYear === year 判断，
只匹配纪念日原始录入年份的那一年。生日/纪念日是周年性事件，应
每年这天都出现。

- 去掉 solarYear === year 判断
- 新增 getAnniversaryDateInYear()：公历直接用 solarMonth/solarDay
- 农历用 lunarToSolar 重算当年公历，因农历对应公历每年浮动
- 当年无闰月时 lunarToSolar 自动忽略 isLeap 回退普通月

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

pages/calendar/calendar.js

@@ -1,8 +1,20 @@
 // calendar.js
 const storage = require('../../utils/storage')
 const dateUtils = require('../../utils/date')
+const lunar = require('../../utils/lunar')
 const { TYPE_NAMES, TYPE_ICONS, IMPORTANCE_COLORS } = require('../../utils/constants')
 
+// 算出某条纪念日在指定年份的公历 (month, day)
+// 公历纪念日：每年同月同日，直接用录入时的 solarMonth/solarDay
+// 农历纪念日：把农历月日转回当年公历，因为农历对应的公历日期每年都不同
+function getAnniversaryDateInYear(a, year) {
+  if (a.isLunar && a.lunarMonth && a.lunarDay) {
+    const date = lunar.lunarToSolar(year, a.lunarMonth, a.lunarDay, !!a.isLeapMonth)
+    return { month: date.getMonth() + 1, day: date.getDate() }
+  }
+  return { month: a.solarMonth, day: a.solarDay }
+}
+
 Page({
   data: {
     currentYear: new Date().getFullYear(),
@@ -27,8 +39,9 @@ Page({
   buildEventIndex(anniversaries, year, month) {
     const index = {}
     for (const a of anniversaries) {
-      if (a.solarYear === year && a.solarMonth === month) {
-        const key = String(a.solarDay)
+      const { month: m, day: d } = getAnniversaryDateInYear(a, year)
+      if (m === month) {
+        const key = String(d)
         if (!index[key]) index[key] = []
         index[key].push(a)
       }
@@ -100,24 +113,25 @@ Page({
     const persons = storage.getPersons()
     const anniversaries = storage.getAnniversaries()
 
-    // 筛选本月纪念日
     const monthEvents = anniversaries
-      .filter(a => a.solarYear === currentYear && a.solarMonth === currentMonth)
       .map(a => {
-        const person = persons.find(p => p.id === a.personId)
-        const date = new Date(currentYear, currentMonth - 1, a.solarDay)
-        const daysUntil = dateUtils.getDaysUntil(date)
-        
+        const { month: m, day: d } = getAnniversaryDateInYear(a, currentYear)
+        return { ...a, _displayMonth: m, _displayDay: d }
+      })
+      .filter(x => x._displayMonth === currentMonth)
+      .map(x => {
+        const person = persons.find(p => p.id === x.personId)
+        const date = new Date(currentYear, x._displayMonth - 1, x._displayDay)
         return {
-          ...a,
+          ...x,
           personName: person ? person.name : '未知',
-          typeIcon: this.getTypeIcon(a.type),
-          typeName: a.customTypeName || this.getTypeName(a.type),
+          typeIcon: this.getTypeIcon(x.type),
+          typeName: x.customTypeName || this.getTypeName(x.type),
           dateText: dateUtils.formatDate(date, 'MM月DD日'),
-          daysUntil
+          daysUntil: dateUtils.getDaysUntil(date)
         }
       })
-      .sort((a, b) => a.solarDay - b.solarDay)
+      .sort((a, b) => a._displayDay - b._displayDay)
 
     this.setData({ monthEvents })
   },