fix(cost): 修复报表日期格式化问题

- 修改了报告日期的格式化逻辑，使用 SimpleDateFormat 替代直接字符串拼接
- 确保日期格式统一为 yyyy-MM 格式进行查询匹配
- 避免了可能的日期格式不一致导致的查询错误

klp-cost/src/main/java/com/klp/cost/service/impl/CostProdReportServiceImpl.java

@@ -71,7 +71,10 @@ public class CostProdReportServiceImpl implements ICostProdReportService {
         lqw.eq(StringUtils.isNotBlank(bo.getLineType()), CostProdReport::getLineType, bo.getLineType());
         lqw.eq(bo.getInputWeight() != null, CostProdReport::getInputWeight, bo.getInputWeight());
         lqw.eq(bo.getOutputWeight() != null, CostProdReport::getOutputWeight, bo.getOutputWeight());
-        lqw.apply(bo.getReportDate() != null, "DATE_FORMAT(report_date, '%Y-%m') = {0}", bo.getReportDate());
+        if (bo.getReportDate() != null) {
+            String monthStr = new java.text.SimpleDateFormat("yyyy-MM").format(bo.getReportDate());
+            lqw.apply("DATE_FORMAT(report_date, '%Y-%m') = {0}", monthStr);
+        }
         return lqw;
     }