Initial commit: Captain Claude Mobile App

- Flutter app with chat and terminal screens
- WebSocket integration for real-time chat
- xterm integration for screen sessions
- Markdown rendering with code blocks
- JWT authentication

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

lib/models/message.dart

@@ -0,0 +1,65 @@
+import 'package:uuid/uuid.dart';
+
+class Message {
+  final String id;
+  final String role; // 'user' or 'assistant'
+  final String content;
+  final DateTime timestamp;
+  final bool isStreaming;
+  final List<String>? attachments;
+
+  Message({
+    String? id,
+    required this.role,
+    required this.content,
+    DateTime? timestamp,
+    this.isStreaming = false,
+    this.attachments,
+  })  : id = id ?? const Uuid().v4(),
+        timestamp = timestamp ?? DateTime.now();
+
+  Message copyWith({
+    String? id,
+    String? role,
+    String? content,
+    DateTime? timestamp,
+    bool? isStreaming,
+    List<String>? attachments,
+  }) {
+    return Message(
+      id: id ?? this.id,
+      role: role ?? this.role,
+      content: content ?? this.content,
+      timestamp: timestamp ?? this.timestamp,
+      isStreaming: isStreaming ?? this.isStreaming,
+      attachments: attachments ?? this.attachments,
+    );
+  }
+
+  factory Message.fromJson(Map<String, dynamic> json) {
+    return Message(
+      id: json['id'],
+      role: json['role'],
+      content: json['content'],
+      timestamp: json['timestamp'] != null
+          ? DateTime.parse(json['timestamp'])
+          : DateTime.now(),
+      attachments: json['attachments'] != null
+          ? List<String>.from(json['attachments'])
+          : null,
+    );
+  }
+
+  Map<String, dynamic> toJson() {
+    return {
+      'id': id,
+      'role': role,
+      'content': content,
+      'timestamp': timestamp.toIso8601String(),
+      'attachments': attachments,
+    };
+  }
+
+  bool get isUser => role == 'user';
+  bool get isAssistant => role == 'assistant';
+}