fix: Use latest dartssh2 and add a switch for temperature between celsius and millicelsius (#1095)

* refactor(sftp): Optimize file download logic and SSH command execution handling

Replace manual chunked downloads with a more concise `sftp.download` method
Consistently use `utf8.decode` to process SSH command output

Remove redundant code and comments, and simplify the logic

* chore: Update `dartssh2` submodule

* feat (Temperature Display): Added an option to switch between degrees Celsius and millicelsius

Allows users to switch temperature units in server settings, resolving the issue of incorrect temperature display on some devices

* chore: Add a participnt

* fix(sftp): Fixed a resource leak issue during file downloads and SSH command execution

Ensured that remote and local file handles are properly closed during file downloads to prevent resource leaks. Additionally, improved error handling during SSH command execution to ensure that all streams are either successfully completed or properly handled in the event of an error.

lib/generated/l10n/l10n_pt.dart

@@ -640,6 +640,10 @@ class AppLocalizationsPt extends AppLocalizations {
   String get specifyDevTip =>
       'Por exemplo, as estatísticas de tráfego de rede são por padrão para todos os dispositivos. Você pode especificar um dispositivo específico aqui.';
 
+  @override
+  String get tempIsCelsiusTip =>
+      'When enabled, the temperature value will be treated as Celsius instead of millicelsius. Turn on only if the temperature displays incorrectly (e.g., showing 0.1°C instead of 58°C).';
+
   @override
   String get speed => 'Velocidade';