feat(settlement): 添加分餐表空数据Excel生成功能

- 引入ZoneId用于获取今日起始时间戳- 过滤订单列表，仅保留今日及以后且支付状态为成功或取消的订单
- 在订单列表或详情为空时，返回空的分餐表Excel文件
- 新增createEmptyExcelBySeparateMeal方法用于生成空数据Excel
- 使用SeparateMealDataDto构建空数据并写入Excel输出流

@@ -61,6 +61,7 @@ import java.math.BigDecimal;
 import java.math.RoundingMode;
 import java.time.LocalDate;
 import java.time.LocalDateTime;
+import java.time.ZoneId;
 import java.time.temporal.ChronoUnit;
 import java.util.ArrayList;
 import java.util.Collections;
@@ -1124,10 +1125,25 @@ public class SettlementServiceImpl implements SettlementService {
 
         // 查询订单列表
         final var queryClientCustomerOrdersByConditionRpcResponse = orderServiceRpcClient.queryClientCustomerOrdersByCondition(queryOrderDto);
-        final var orderList = queryClientCustomerOrdersByConditionRpcResponse.getResponsesList();
+
+        // 今天开始时间的时间戳（毫秒）
+        final long todayStartTimestamp = LocalDate.now().atStartOfDay()
+                .atZone(ZoneId.systemDefault())
+                .toInstant()
+                .toEpochMilli();
+
+        final var orderList = queryClientCustomerOrdersByConditionRpcResponse.getResponsesList()
+                .stream()
+                .filter(e -> {
+                    boolean payStatusMatch = e.getPayStatus() == PayStatusEnum.SUCCEED|| e.getPayStatus() == PayStatusEnum.PAY_CANCELED;
+                    // 过滤时间：只查询今天和以后的订单
+                    boolean timeMatch = e.getMealTime() >= todayStartTimestamp;
+                    return payStatusMatch && timeMatch;
+                })
+                .toList();
         if (orderList.isEmpty()) {
             log.warn("未查询到订单数据，enterpriseId: {}", enterpriseId);
-            return null;
+            return createEmptyExcelBySeparateMeal();
         }
 
         // 获取订单IDs
@@ -1145,7 +1161,7 @@ public class SettlementServiceImpl implements SettlementService {
         final var orderDetailList = orderServiceRpcClient.getOrderDetailsByOrderIds(orderIds);
         if (orderDetailList == null || orderDetailList.isEmpty()) {
             log.warn("未查询到订单详情数据，orderIds: {}", orderIds);
-            return null;
+            return createEmptyExcelBySeparateMeal();
         }
 
         // 订单详情按订单ID分组
@@ -1443,4 +1459,19 @@ public class SettlementServiceImpl implements SettlementService {
         return outputStream;
     }
 
+    /**
+     * 创建空的分餐表Excel（无数据）
+     */
+    private static ByteArrayOutputStream createEmptyExcelBySeparateMeal() {
+        try {
+            SeparateMealDataDto emptyData = SeparateMealDataDto.builder()
+                    .mealDetails(new ArrayList<>())
+                    .build();
+            return writeToExcelBySeparateMeal(emptyData);
+        } catch (IOException e) {
+            log.error("创建空分餐表Excel失败", e);
+            throw BusinessException.build(ErrorCodeEnum.GENERATE_EXCEL_ERROR);
+        }
+    }
+
 }