ConfirmAction.title defaults to empty (a dialogId confirm doesn't need it)

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019VxYXZ8ycVxLBPATD7fXGw

Author: claude

lib/src/api/models/action/confirm_action.dart

@@ -199,7 +199,7 @@ class ConfirmAction extends ActionModel with Equatable, SerializableMixin {
 
   /// Creates a [ConfirmAction].
   ConfirmAction({
-    required this.title,
+    this.title = '',
     this.caption = '',
     this.captionStyle,
     this.message = '',