feat: Enhance Face AI upload functionality and UI

- Updated MainWindow.axaml to increase height and add new UI elements for SSH upload configuration.
- Implemented commands for opening source and destination paths in file explorer.
- Added FaceUploadPath and SSH configuration properties to DataModel and AiSettingsViewModel.
- Introduced validation for FaceUploadPath format and commands for uploading face encoder output.
- Enhanced PickerPreferenceService to manage SSH credentials and upload preferences.
- Updated settings persistence to include FaceUploadPath and SSH preferences.
- Added tests for FaceUploadPath validation and upload command enabling logic.

MaddoShared/PicSettings.cs

@@ -10,6 +10,7 @@ public class PicSettings
     public string DirectoryDestinazione { get; set; }
     public string TestoFirmaStart { get; set; }
     public string TestoFirmaStartV { get; set; }
+    public byte[]? LogoData { get; set; }
     public DateTime DataPartenza { get; set; }
     public string TestoOrario { get; set; }
     public int DimStandard { get; set; }