New feat

- SFTP download
- open downloaded files in other apps

lib/data/provider/sftp_download.dart

@@ -0,0 +1,31 @@
+import 'package:toolbox/core/provider_base.dart';
+import 'package:toolbox/data/model/sftp/download_status.dart';
+import 'package:toolbox/data/model/sftp/download_worker.dart';
+
+class SftpDownloadProvider extends ProviderBase {
+  final List<SftpDownloadStatus> _status = [];
+  List<SftpDownloadStatus> get status => _status;
+
+  List<SftpDownloadStatus> gets({int? id, String? fileName}) {
+    var found = <SftpDownloadStatus>[];
+    if (id != null) {
+      found = _status.where((e) => e.id == id).toList();
+    }
+    if (fileName != null) {
+      found = found
+          .where((e) => e.item.localPath.split('/').last == fileName)
+          .toList();
+    }
+    return found;
+  }
+
+  SftpDownloadStatus? get({int? id, String? name}) {
+    final found = gets(id: id, fileName: name);
+    if (found.isEmpty) return null;
+    return found.first;
+  }
+
+  void add(DownloadItem item, {String? key}) {
+    _status.add(SftpDownloadStatus(item, notifyListeners, key: key));
+  }
+}