feat: payload для /start в ботах.

lib/models/attachment.dart

@@ -429,6 +429,8 @@ class LocationAttachment extends MessageAttachment {
 }
 
 class ControlAttachment extends MessageAttachment {
+  static const String botStartedEvent = 'botStarted';
+
   final String? event;
   final String? title;
   final List<int>? userIds;
@@ -444,6 +446,8 @@ class ControlAttachment extends MessageAttachment {
     this.userId,
   }) : super(type: AttachmentType.control);
 
+  bool get isBotStart => event == botStartedEvent;
+
   factory ControlAttachment.fromMap(Map<String, dynamic> map) {
     String? title = map['title']?.toString();
     if ((title == null || title.isEmpty) && map['shortMessage'] != null) {

lib/models/bot_info.dart

@@ -0,0 +1,48 @@
+import 'contact_info.dart';
+
+class BotCommand {
+  final String name;
+  final String? description;
+
+  const BotCommand({required this.name, this.description});
+
+  factory BotCommand.fromMap(Map map) => BotCommand(
+    name: map['name']?.toString() ?? '',
+    description: (map['description'] as String?)?.trim().isNotEmpty == true
+        ? (map['description'] as String).trim()
+        : null,
+  );
+
+  String get slash => '/$name';
+}
+
+class BotInfo {
+  final int botId;
+  final List<BotCommand> commands;
+  final ContactInfo? contact;
+
+  const BotInfo({required this.botId, required this.commands, this.contact});
+
+  factory BotInfo.fromPayload(int botId, Map<String, dynamic> payload) {
+    final rawCommands = payload['commands'];
+    final commands = <BotCommand>[];
+    if (rawCommands is List) {
+      for (final c in rawCommands.whereType<Map>()) {
+        final command = BotCommand.fromMap(c);
+        if (command.name.isNotEmpty) commands.add(command);
+      }
+    }
+    final rawContact = payload['contact'];
+    return BotInfo(
+      botId: botId,
+      commands: commands,
+      contact: rawContact is Map
+          ? ContactInfo.fromMap(Map<String, dynamic>.from(rawContact))
+          : null,
+    );
+  }
+
+  String? get description => contact?.raw['description'] as String?;
+
+  String? get link => contact?.raw['link'] as String?;
+}