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/user.dart

@@ -0,0 +1,29 @@
+class User {
+  final String username;
+  final String token;
+  final DateTime expiresAt;
+
+  User({
+    required this.username,
+    required this.token,
+    required this.expiresAt,
+  });
+
+  bool get isExpired => DateTime.now().isAfter(expiresAt);
+
+  factory User.fromJson(Map<String, dynamic> json) {
+    return User(
+      username: json['username'],
+      token: json['token'],
+      expiresAt: DateTime.parse(json['expires_at']),
+    );
+  }
+
+  Map<String, dynamic> toJson() {
+    return {
+      'username': username,
+      'token': token,
+      'expires_at': expiresAt.toIso8601String(),
+    };
+  }
+}