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_me.dart

@@ -20,9 +20,9 @@ import '../../utils/util_web.dart'
     if (dart.library.io) '../../utils/util_io.dart';
 import '../../utils/utils.dart';
 
-MediaQueryData mediaQuery;
-double statusBarHeight;
-double screenHeight;
+late MediaQueryData mediaQuery;
+late double statusBarHeight;
+late double screenHeight;
 
 class MobileMe extends StatefulWidget {
   final Key? key;
@@ -36,18 +36,18 @@ class MobileMe extends StatefulWidget {
 }
 
 class MobileMeState extends State<MobileMe> {
-  int userId;
-  String accessToken;
+  late int userId;
+  late String accessToken;
 
-  bool isLoading;
-  User _user;
+  late bool isLoading;
+  late User _user;
 
-  ShopScrollCoordinator _shopCoordinator;
-  ShopScrollController _pageScrollController;
+  late ShopScrollCoordinator _shopCoordinator;
+  late ShopScrollController _pageScrollController;
   final double _sliverAppBarInitHeight = 165.0;
   final double _appBarHeight = 85.0;
 
-  ShopScrollController _listScrollController1;
+  late ShopScrollController _listScrollController1;
 
   @override
   Widget build(BuildContext context) {
@@ -88,7 +88,7 @@ class MobileMeState extends State<MobileMe> {
           children: <Widget>[
             Container(
               margin: EdgeInsets.only(right: 5.0),
-              child: _user != null && _user.avatarUrl.isNotEmpty
+              child: _user != null && _user.avatarUrl!.isNotEmpty
                   ? Util.showImage(
                       'https:${_user.avatarUrl}',
                       width: 60,
@@ -219,7 +219,7 @@ class MobileMeState extends State<MobileMe> {
                             Container(
                               child: Text(
                                 _user != null
-                                    ? '${_user.wallet.toStringAsFixed(2)}'
+                                    ? '${_user.wallet!.toStringAsFixed(2)}'
                                     : '0.00',
                                 style: TextStyle(
                                   fontSize: 24.0,
@@ -671,7 +671,7 @@ class MobileMeState extends State<MobileMe> {
                       ),
                       onTap: () {
                         if (_user != null) {
-                          if (_user.email == null || _user.email.isEmpty) {
+                          if (_user.email == null || _user.email!.isEmpty) {
                             showDialog(
                                 context: context,
                                 builder: (BuildContext context) {