fix(problem_report_message): fix problem report message entity

implemented missing fields of the problem report message entity
https://iden3-communication.io/report-problem/2.0/report-problem-message/

lib/iden3comm/domain/entities/common/response/problem_report_message_entity.dart

@@ -1,11 +1,19 @@
 import 'package:polygonid_flutter_sdk/iden3comm/domain/entities/common/iden3_message_entity.dart';
 
 class ProblemReportMessageEntity extends Iden3MessageEntity<ProblemReportBody> {
+  // Parent thread
+  final String pthid;
+
+  // List of IDs of previous messages that triggered this one
+  final List<String>? ack;
+
   ProblemReportMessageEntity({
     required super.id,
     required super.typ,
     required super.type,
     required super.thid,
+    required this.pthid,
+    required this.ack,
     required super.from,
     required super.body,
   }) : super(messageType: Iden3MessageType.problemReport);
@@ -18,6 +26,8 @@ class ProblemReportMessageEntity extends Iden3MessageEntity<ProblemReportBody> {
       typ: json['typ'],
       type: json['type'],
       thid: json['thid'],
+      pthid: json['pthid'],
+      ack: json['ack'].map<String>((e) => e.toString()).toList(),
       from: "",
       body: body,
     );
@@ -27,6 +37,8 @@ class ProblemReportMessageEntity extends Iden3MessageEntity<ProblemReportBody> {
   Map<String, dynamic> toJson() {
     final Map<String, dynamic> data = super.toJson();
     data['body'] = body.toJson();
+    data['pthid'] = pthid;
+    data['ack'] = ack;
     return data;
   }
 
@@ -42,37 +54,55 @@ class ProblemReportMessageEntity extends Iden3MessageEntity<ProblemReportBody> {
 }
 
 class ProblemReportBody {
+  // (optional) List of arguments matching the placeholders in comment field
+  final List<String>? args;
+
+  // (required) Problem code (See Problem Codes section)
   final String code;
+
+  // (optional) Human-friendly text describing the problem. Can include {1} placeholders {2}
   final String? comment;
 
+  // (optional) URI where more help about the problem could be received
+  final String? escalateTo;
+
   ProblemReportBody({
+    this.args,
     required this.code,
     this.comment,
+    this.escalateTo,
   });
 
   factory ProblemReportBody.fromJson(Map<String, dynamic> json) {
     return ProblemReportBody(
+      args: json['args'].map<String>((e) => e.toString()).toList(),
       code: json['code'],
       comment: json['comment'],
+      escalateTo: json['escalate_to'],
     );
   }
 
   Map<String, dynamic> toJson() {
     return {
       'code': code,
+      if (args != null) 'args': args,
+      if (escalateTo != null) 'escalate_to': escalateTo,
       if (comment != null) 'comment': comment,
     };
   }
 
   @override
-  String toString() => "[ProblemReportBody] {code: $code, comment: $comment}";
+  String toString() =>
+      "[ProblemReportBody] {code: $code, comment: $comment, args: $args, escalateTo: $escalateTo}";
 
   @override
   bool operator ==(Object other) =>
       identical(this, other) ||
       other is ProblemReportBody &&
           runtimeType == other.runtimeType &&
           code == other.code &&
+          escalateTo == other.escalateTo &&
+          args == other.args &&
           comment == other.comment;
 
   @override