set calculation expiry date initialized as today's date

src/components/StockIn/CalculateExpiryDateModal.tsx

@@ -142,6 +142,16 @@ const CalculateExpiryDateModal: React.FC<Props> = ({
         }
     }, [productionDate, shelfLife, expiryDate]);
 
+    useEffect(() => {
+        if (!open) return;
+        const today = dayjs();
+        // only set if different to avoid loop
+        setProductionDate(prev => (prev && prev.isSame(today, "day") ? prev : today));
+        if (shelfLife !== undefined) {
+            setExpiryDate(today.add(shelfLife, "day"));
+        }
+    }, [open, shelfLife]);
+
     return (
         <Modal
             open={open}