Add manual auth screen

moneymgr_mobile/lib/widgets/app_button.dart

@@ -6,25 +6,23 @@ import 'package:flutter_hooks/flutter_hooks.dart';
 import 'package:moneymgr_mobile/utils/extensions.dart';
 import 'package:moneymgr_mobile/utils/hooks.dart';
 
-
 /// A button that shows a circular progress indicator when the [onPressed] callback
 /// is pending.
 class AppButton extends HookWidget {
-  const AppButton({
-    super.key,
-    required this.onPressed,
-    required this.label,
-  });
+  const AppButton({super.key, required this.onPressed, required this.label});
 
   final AsyncCallback? onPressed;
   final String label;
 
   @override
   Widget build(BuildContext context) {
-    final (:pending, :snapshot, hasError: _) = useAsyncTask();
+    final (:pending, :snapshot, :hasError) = useAsyncTask();
 
     return FilledButton(
       onPressed: onPressed == null ? null : () => pending.value = onPressed!(),
+      style: ButtonStyle(
+        backgroundColor: hasError ? WidgetStatePropertyAll(Colors.red) : null,
+      ),
       child: SeparatedRow(
         separatorBuilder: () => const GutterSmall(),
         mainAxisAlignment: MainAxisAlignment.center,