fix(store-hours): reject overlapping holiday date ranges

src/Api/TakeoutSaaS.TenantApi/Controllers/StoreHoursController.cs

@@ -164,6 +164,22 @@ public sealed class StoreHoursController(
         }
 
         var holidayId = StoreApiHelpers.ParseSnowflakeOrNull(holidayInput.Id);
+
+        // 同一门店的特殊日期范围不允许重叠（编辑时排除自身）。
+        var hasOverlap = await dbContext.StoreHolidays
+            .AsNoTracking()
+            .AnyAsync(
+                x => x.TenantId == tenantId
+                     && x.StoreId == parsedStoreId
+                     && (!holidayId.HasValue || x.Id != holidayId.Value)
+                     && x.Date <= endDate
+                     && (x.EndDate ?? x.Date) >= startDate,
+                cancellationToken);
+        if (hasOverlap)
+        {
+            throw new BusinessException(ErrorCodes.ValidationFailed, "日期范围与已有节假日/特殊日期冲突，请勿重复设置");
+        }
+
         var entity = holidayId.HasValue
             ? await dbContext.StoreHolidays.FirstOrDefaultAsync(
                 x => x.Id == holidayId.Value && x.TenantId == tenantId && x.StoreId == parsedStoreId,