TF-2764 Support press Escape shortcut key on keyboard to close viewer

lib/features/email/presentation/widgets/pdf_viewer/pdf_viewer.dart

@@ -60,6 +60,7 @@ class _PDFViewerState extends State<PDFViewer> {
   final ValueNotifier<Object?> _pdfViewStateNotifier = ValueNotifier<Object?>(null);
 
   final DeviceInfoPlugin _deviceInfoPlugin = Get.find<DeviceInfoPlugin>();
+  final FocusNode _keyboardFocusNode = FocusNode();
 
   @override
   void initState() {
@@ -116,12 +117,17 @@ class _PDFViewerState extends State<PDFViewer> {
     _downloadInteractorStreamSubscription?.cancel();
     _downloadInteractorStreamSubscription = null;
     _downloadAttachmentCancelToken = null;
+    _keyboardFocusNode.dispose();
     super.dispose();
   }
 
   @override
   Widget build(BuildContext context) {
-    return Center(
+    return RawKeyboardListener(
+      focusNode: _keyboardFocusNode,
+      autofocus: true,
+      onKey: _handleKeyboardEventListener,
+      child: Center(
         child: Stack(
           children: [
             Center(
@@ -272,6 +278,7 @@ class _PDFViewerState extends State<PDFViewer> {
             ),
           ],
         ),
+      ),
     );
   }
 
@@ -279,4 +286,10 @@ class _PDFViewerState extends State<PDFViewer> {
     _downloadAttachmentCancelToken?.cancel();
     Navigator.maybeOf(context)?.pop();
   }
+
+  void _handleKeyboardEventListener(RawKeyEvent event) {
+    if (event is RawKeyDownEvent && event.logicalKey == LogicalKeyboardKey.escape) {
+      _closeView();
+    }
+  }
 }

test/features/email/presentation/controller/single_email_controller_test.dart

@@ -8,6 +8,9 @@ import 'package:jmap_dart_client/jmap/account_id.dart';
 import 'package:jmap_dart_client/jmap/core/capability/calendar_event_capability.dart';
 import 'package:jmap_dart_client/jmap/core/capability/capability_identifier.dart';
 import 'package:jmap_dart_client/jmap/core/id.dart';
+import 'package:jmap_dart_client/jmap/core/session/session.dart';
+import 'package:jmap_dart_client/jmap/core/state.dart';
+import 'package:jmap_dart_client/jmap/core/user_name.dart';
 import 'package:jmap_dart_client/jmap/mail/calendar/calendar_event.dart';
 import 'package:jmap_dart_client/jmap/mail/calendar/reply/calendar_event_accept_response.dart';
 import 'package:jmap_dart_client/jmap/mail/email/email.dart';