重构首页与tabBar：老黄历大日历+月历切换，新增百科页

tabBar（5个，全部带图标）：
- 老黄历(首页) / 许愿 / 八字 / 百科(新) / 我的(原设置)
- 移除日历tab，月历并入首页左上角切换
- 移除运势tab，改从'我的'页进入

首页重构：
- custom 导航栏，标题'老黄历'
- 老式万年历大日历卡片：大日期+农历+干支+宜忌
- 左右箭头切换日期，'回到今天'
- 左上角'月历/日历'切换按钮，月历视图复用原日历网格
- 月历点选日期自动切回日视图

新增百科页：
- 二十四节气/农历节日/公历节日/干支生肖/黄历术语 分类
- 搜索 + 展开详情

我的页（原设置）：
- 新增功能入口：每日运势/占卜/二十四节气/月历视图

mini/pages/home/home.js

@@ -1,28 +1,116 @@
-const { getTodayInfo, getAlmanacInfo } = require('../../utils/core/index.js');
+const { getDayInfo, getAlmanacInfo, getMonthCalendar } = require('../../utils/core/index.js');
+
+function pad(n) { return String(n).padStart(2, '0'); }
+function fmt(y, m, d) { return `${y}-${pad(m)}-${pad(d)}`; }
 
 Page({
   data: {
+    statusBarHeight: 20,
+    navBarHeight: 44,
+    viewMode: 'day',          // day | month
     dayInfo: {},
-    almanac: {}
+    almanac: {},
+    // 月历
+    year: 0,
+    month: 0,
+    weekHeaders: ['日', '一', '二', '三', '四', '五', '六'],
+    calendarDays: [],
+    selectedDay: null
   },
 
   onLoad() {
-    this.loadData();
+    const sys = wx.getWindowInfo ? wx.getWindowInfo() : wx.getSystemInfoSync();
+    const menu = wx.getMenuButtonBoundingClientRect ? wx.getMenuButtonBoundingClientRect() : null;
+    const statusBarHeight = sys.statusBarHeight || 20;
+    let navBarHeight = 44;
+    if (menu && menu.top) {
+      navBarHeight = (menu.top - statusBarHeight) * 2 + menu.height;
+    }
+    this.setData({ statusBarHeight, navBarHeight });
+    this.loadDay(new Date());
   },
 
   onPullDownRefresh() {
-    this.loadData();
+    if (this.data.viewMode === 'day') {
+      this.loadDay(new Date());
+    } else {
+      this.loadCalendar();
+    }
     wx.stopPullDownRefresh();
   },
 
-  loadData() {
-    const dayInfo = getTodayInfo();
-    const almanac = getAlmanacInfo(dayInfo.solarYear, dayInfo.solarMonth, dayInfo.solarDay);
-    this.setData({ dayInfo, almanac });
+  /** 加载某日的老黄历 */
+  loadDay(date) {
+    const y = date.getFullYear();
+    const m = date.getMonth() + 1;
+    const d = date.getDate();
+    const dayInfo = getDayInfo(y, m, d);
+    const almanac = getAlmanacInfo(y, m, d);
+    this.setData({ dayInfo, almanac, year: y, month: m });
+  },
+
+  /** 前一天 / 后一天 */
+  prevDay() { this.shiftDay(-1); },
+  nextDay() { this.shiftDay(1); },
+  shiftDay(delta) {
+    const { dayInfo } = this.data;
+    const date = new Date(dayInfo.solarYear, dayInfo.solarMonth - 1, dayInfo.solarDay + delta);
+    this.loadDay(date);
+  },
+
+  /** 回到今天 */
+  backToday() {
+    this.loadDay(new Date());
+  },
+
+  /** 切换 日视图/月历视图 */
+  toggleView() {
+    const mode = this.data.viewMode === 'day' ? 'month' : 'day';
+    this.setData({ viewMode: mode });
+    if (mode === 'month') {
+      const { dayInfo } = this.data;
+      this.setData({ year: dayInfo.solarYear, month: dayInfo.solarMonth }, () => this.loadCalendar());
+    }
+  },
+
+  /** 月历 */
+  loadCalendar() {
+    const { year, month } = this.data;
+    const weeks = getMonthCalendar(year, month);
+    const calendarDays = [];
+    weeks.forEach(w => w.forEach(d => calendarDays.push(d)));
+    this.setData({ calendarDays });
+  },
+
+  prevMonth() {
+    let { year, month } = this.data;
+    month--;
+    if (month < 1) { month = 12; year--; }
+    this.setData({ year, month }, () => this.loadCalendar());
+  },
+
+  nextMonth() {
+    let { year, month } = this.data;
+    month++;
+    if (month > 12) { month = 1; year++; }
+    this.setData({ year, month }, () => this.loadCalendar());
+  },
+
+  /** 月历中选中某天 → 切回日视图 */
+  selectDay(e) {
+    const date = e.currentTarget.dataset.date;
+    const [y, m, d] = date.split('-').map(Number);
+    this.loadDay(new Date(y, m - 1, d));
+    this.setData({ viewMode: 'day' });
+  },
+
+  /** 跳详情页 */
+  goDetail() {
+    const { dayInfo } = this.data;
+    wx.navigateTo({ url: `/pages/day-detail/day-detail?date=${fmt(dayInfo.solarYear, dayInfo.solarMonth, dayInfo.solarDay)}` });
   },
 
   navTo(e) {
-    const url = e.currentTarget.dataset.url;
-    wx.navigateTo({ url });
+    wx.navigateTo({ url: e.currentTarget.dataset.url });
   }
 });