feat(日历): 添加交易热力图组件展示每日交易统计

- 新增 ContributionHeatmap 组件实现类似 GitHub 贡献热力图的可视化
- 添加 getDailyStatisticsRange API 接口获取日期范围内的每日统计数据
- 调整日历页面布局以容纳热力图组件
- 热力图支持动态阈值计算和暗黑模式适配
- 交易变更时自动刷新热力图数据

Web/src/views/CalendarView.vue

@@ -10,6 +10,8 @@
       @month-show="onMonthShow"
       @select="onDateSelect"
     />
+    
+    <ContributionHeatmap ref="heatmapRef" />
 
     <!-- 日期交易列表弹出层 -->
     <PopupContainer
@@ -53,6 +55,7 @@ import TransactionList from "@/components/TransactionList.vue";
 import TransactionDetail from "@/components/TransactionDetail.vue";
 import SmartClassifyButton from "@/components/SmartClassifyButton.vue";
 import PopupContainer from "@/components/PopupContainer.vue";
+import ContributionHeatmap from "@/components/ContributionHeatmap.vue";
 
 const dailyStatistics = ref({});
 const listVisible = ref(false);
@@ -62,6 +65,7 @@ const currentTransaction = ref(null);
 const listLoading = ref(false);
 const selectedDate = ref(null);
 const selectedDateText = ref("");
+const heatmapRef = ref(null);
 
 // 设置日历可选范围（例如：过去2年到未来1年）
 const minDate = new Date(new Date().getFullYear() - 2, 0, 1); // 2年前的1月1日
@@ -71,7 +75,7 @@ onMounted(async () => {
   await nextTick();
   setTimeout(() => {
     // 计算页面高度，滚动3/4高度以显示更多日期
-    const height = document.querySelector(".calendar-container").clientHeight * 0.45;
+    const height = document.querySelector(".calendar-container").clientHeight * 0.55;
     document.querySelector(".van-calendar__body").scrollBy({
       top: -height,
       behavior: "smooth",
@@ -266,6 +270,7 @@ const onGlobalTransactionDeleted = () => {
   }
   const now = selectedDate.value || new Date()
   fetchDailyStatistics(now.getFullYear(), now.getMonth() + 1)
+  heatmapRef.value?.refresh()
 }
 
 window.addEventListener && window.addEventListener('transaction-deleted', onGlobalTransactionDeleted)
@@ -281,6 +286,7 @@ const onGlobalTransactionsChanged = () => {
   }
   const now = selectedDate.value || new Date()
   fetchDailyStatistics(now.getFullYear(), now.getMonth() + 1)
+  heatmapRef.value?.refresh()
 }
 
 window.addEventListener && window.addEventListener('transactions-changed', onGlobalTransactionsChanged)
@@ -304,10 +310,11 @@ onBeforeUnmount(() => {
   overflow: hidden;
   margin: 0;
   padding: 0;
+  background-color: var(--van-background);
 }
 
 .calendar-container :deep(.van-calendar) {
-  height: 100% !important;
+  height: auto !important;
   flex: 1;
   overflow: auto;
   margin: 0;