fix

Service/Transaction/TransactionStatisticsService.cs

@@ -32,8 +32,22 @@ public class TransactionStatisticsService(
 {
     public async Task<Dictionary<string, (int count, decimal expense, decimal income, decimal saving)>> GetDailyStatisticsAsync(int year, int month, string? savingClassify = null)
     {
-        var startDate = new DateTime(year, month, 1);
-        var endDate = startDate.AddMonths(1);
+        // 当 month=0 时，表示查询整年数据
+        DateTime startDate;
+        DateTime endDate;
+        
+        if (month == 0)
+        {
+            // 查询整年：1月1日至12月31日
+            startDate = new DateTime(year, 1, 1);
+            endDate = new DateTime(year, 12, 31).AddDays(1); // 包含12月31日
+        }
+        else
+        {
+            // 查询指定月份
+            startDate = new DateTime(year, month, 1);
+            endDate = startDate.AddMonths(1);
+        }
 
         return await GetDailyStatisticsByRangeAsync(startDate, endDate, savingClassify);
     }