feat: Implement accessible SFTP file browser and native editor

lib/ui/views/connection_view.dart

@@ -23,8 +23,11 @@ class _ConnectionViewState extends ConsumerState<ConnectionView> {
     // Listen for global connection errors (e.g. lost connection)
     ref.listen<String?>(connectionErrorProvider, (previous, next) {
       if (next != null) {
-        _showErrorDialog(next);
-        ref.read(connectionErrorProvider.notifier).state = null;
+        SemanticsService.sendAnnouncement(
+          View.of(context),
+          next,
+          TextDirection.ltr,
+        );
       }
     });
 
@@ -252,6 +255,7 @@ class _NewConnectionFormState extends ConsumerState<NewConnectionForm> {
   }
 
   Future<void> _pickKeyFile() async {
+    final view = View.of(context);
     try {
       FilePickerResult? result = await FilePicker.platform.pickFiles(
         type: FileType.any, // SSH keys often have no extension or .pem/.key
@@ -265,7 +269,11 @@ class _NewConnectionFormState extends ConsumerState<NewConnectionForm> {
             _privateKeyContent = content;
             _privateKeyName = file.name;
           });
-          SemanticsService.announce('Key selected: ${file.name}', TextDirection.ltr);
+          SemanticsService.sendAnnouncement(
+            view,
+            'Key selected: ${file.name}',
+            TextDirection.ltr,
+          );
         }
       }
     } catch (e) {