feat: adopt material 3 theme and billing adjustments

lib/widgets/sms_scan/scan_initial_widget.dart

@@ -1,5 +1,5 @@
 import 'package:flutter/material.dart';
-import '../../theme/app_colors.dart';
+// import '../../theme/app_colors.dart';
 import '../../widgets/themed_text.dart';
 import '../../widgets/common/buttons/primary_button.dart';
 import '../../widgets/native_ad_widget.dart';
@@ -32,7 +32,7 @@ class ScanInitialWidget extends StatelessWidget {
                   padding: const EdgeInsets.only(bottom: 24.0),
                   child: ThemedText(
                     errorMessage!,
-                    color: Colors.red,
+                    color: Theme.of(context).colorScheme.error,
                     textAlign: TextAlign.center,
                   ),
                 ),
@@ -59,7 +59,7 @@ class ScanInitialWidget extends StatelessWidget {
                 onPressed: onScanPressed,
                 width: 200,
                 height: 56,
-                backgroundColor: AppColors.primaryColor,
+                backgroundColor: Theme.of(context).colorScheme.primary,
               ),
             ],
           ),