phase3: nullfix.py batch script — bang/late/param-nullable

Automated null-safety fixes driven by dart analyze (no corruption):
- unchecked_use_of_nullable_value: insert '!' on receiver (property/method/[]/op)
- not_initialized field/var: mark 'late'
- missing_default_value_for_parameter: nullable param
Errors: 2374(peak) -> 907

lib/widgets/mobile/mobile_orders.dart

@@ -152,7 +152,7 @@ class MobileOrdersState extends State<MobileOrders> with SingleTickerProviderSta
         row.children.add(Expanded(
           child: Container(
             child: Text(
-              order.cartInfo.productList[0].name,
+              order.cartInfo!.productList![0].name,
               style: TextStyle(
                 fontSize: 14.0,
               ),
@@ -161,7 +161,7 @@ class MobileOrdersState extends State<MobileOrders> with SingleTickerProviderSta
             ),
           ),
         ));
-        if (order.cartInfo.productList.length > 1) {
+        if (order.cartInfo!.productList!.length > 1) {
           row.children.add(Container(
             child: Text(
               S.of(context).and_more_item_token(Utils.getProductLineInOrder(order.cartInfo)),
@@ -176,7 +176,7 @@ class MobileOrdersState extends State<MobileOrders> with SingleTickerProviderSta
           width: 80.0,
           alignment: Alignment.centerRight,
           child: Text(
-            '\$${order.totalPrice.toStringAsFixed(2)}',
+            '\$${order.totalPrice!.toStringAsFixed(2)}',
             style: TextStyle(
               fontSize: 16.0,
               fontWeight: FontWeight.bold,
@@ -291,7 +291,7 @@ class MobileOrdersState extends State<MobileOrders> with SingleTickerProviderSta
                 mainAxisAlignment: MainAxisAlignment.start,
                 children: <Widget>[
                   Container(
-                    child: Util.showImage('${order.cartInfo.businessInfo.picUrl}',
+                    child: Util.showImage('${order.cartInfo!.businessInfo!.picUrl}',
                       width: 32.0,
                       height: 32.0,
                       fit: BoxFit.fill,
@@ -307,7 +307,7 @@ class MobileOrdersState extends State<MobileOrders> with SingleTickerProviderSta
                           children: <Widget>[
                             Container(
                               child: Text(
-                                '${order.cartInfo.businessInfo.name}',
+                                '${order.cartInfo!.businessInfo!.name}',
                                 style: TextStyle(
                                   fontSize: 20.0,
                                 ),