feat(预算): 添加预算趋势分析功能并优化图表展示

重构预算分析图表组件，添加每日/每月趋势统计功能：
1. 在Repository层添加趋势统计接口
2. 在Service层实现趋势数据计算逻辑
3. 优化前端图表展示，合并偏差分析图表
4. 改进燃尽图使用实际趋势数据
5. 调整UI样式和交互体验

Repository/TransactionRecordRepository.cs

@@ -198,6 +198,16 @@ public interface ITransactionRecordRepository : IBaseRepository<TransactionRecor
     /// <returns>影响行数</returns>
     Task<int> ConfirmAllUnconfirmedAsync(long[] ids);
 
+    /// <summary>
+    /// 获取指定分类在指定时间范围内的每日/每月统计趋势
+    /// </summary>
+    Task<Dictionary<DateTime, decimal>> GetFilteredTrendStatisticsAsync(
+        DateTime startDate,
+        DateTime endDate,
+        TransactionType type,
+        IEnumerable<string> classifies,
+        bool groupByMonth = false);
+
     /// <summary>
     /// 更新分类名称
     /// </summary>
@@ -719,6 +729,37 @@ public class TransactionRecordRepository(IFreeSql freeSql) : BaseRepository<Tran
             .Where(t => ids.Contains(t.Id))
             .ExecuteAffrowsAsync();
     }
+
+    public async Task<Dictionary<DateTime, decimal>> GetFilteredTrendStatisticsAsync(
+        DateTime startDate,
+        DateTime endDate,
+        TransactionType type,
+        IEnumerable<string> classifies,
+        bool groupByMonth = false)
+    {
+        var query = FreeSql.Select<TransactionRecord>()
+            .Where(t => t.OccurredAt >= startDate && t.OccurredAt <= endDate && t.Type == type);
+
+        if (classifies != null && classifies.Any())
+        {
+            query = query.Where(t => classifies.Contains(t.Classify));
+        }
+
+        var list = await query.ToListAsync(t => new { t.OccurredAt, t.Amount });
+
+        if (groupByMonth)
+        {
+            return list
+                .GroupBy(t => new DateTime(t.OccurredAt.Year, t.OccurredAt.Month, 1))
+                .ToDictionary(g => g.Key, g => g.Sum(x => Math.Abs(x.Amount)));
+        }
+        else
+        {
+            return list
+                .GroupBy(t => t.OccurredAt.Date)
+                .ToDictionary(g => g.Key, g => g.Sum(x => Math.Abs(x.Amount)));
+        }
+    }
 }
 
 /// <summary>