базовая логика скачивания обновлений

lib/features/launcher/domain/entities/launcher_session.dart

@@ -0,0 +1,27 @@
+final class LauncherSession {
+  final String accessToken;
+  final String tokenType;
+  final DateTime? expiresAt;
+
+  const LauncherSession({
+    required this.accessToken,
+    required this.tokenType,
+    required this.expiresAt,
+  });
+
+  factory LauncherSession.fromJson(Map<String, dynamic> json) {
+    return LauncherSession(
+      accessToken: json['access_token'] as String? ?? '',
+      tokenType: json['token_type'] as String? ?? 'Bearer',
+      expiresAt: _parseDateTime(json['expires_at'] as String?),
+    );
+  }
+
+  static DateTime? _parseDateTime(String? rawValue) {
+    if (rawValue == null || rawValue.isEmpty) {
+      return null;
+    }
+
+    return DateTime.tryParse(rawValue);
+  }
+}