Refactor path handling in UI components

- Removed redundant folder and file opening methods from AiTabView and FaceAiTabView.
- Introduced PathPickerField control to streamline path selection and opening functionality across multiple views.
- Updated FaceAiTabView and GeneralTabView to utilize PathPickerField for source and destination path selection.
- Created PathShellService to encapsulate logic for opening paths in the file explorer.
- Simplified XAML structure by replacing manual grid definitions with PathPickerField components.
- Removed unused namespaces and cleaned up code for better readability and maintainability.

imagecatalog/AvaloniaViews/GeneralTabView.axaml.cs

@@ -1,9 +1,4 @@
 using Avalonia.Controls;
-using Avalonia.Interactivity;
-using System;
-using System.Diagnostics;
-using System.IO;
-
 namespace ImageCatalog_2.AvaloniaViews;
 
 public partial class GeneralTabView : Avalonia.Controls.UserControl
@@ -12,45 +7,4 @@ public partial class GeneralTabView : Avalonia.Controls.UserControl
     {
         InitializeComponent();
     }
-
-    private void OpenSourceFolder_Click(object? sender, RoutedEventArgs e)
-    {
-        if (DataContext is DataModel model)
-        {
-            OpenInExplorer(model.SourcePath);
-        }
-    }
-
-    private void OpenDestinationFolder_Click(object? sender, RoutedEventArgs e)
-    {
-        if (DataContext is DataModel model)
-        {
-            OpenInExplorer(model.DestinationPath);
-        }
-    }
-
-    private static void OpenInExplorer(string? path)
-    {
-        if (string.IsNullOrWhiteSpace(path))
-        {
-            return;
-        }
-
-        var normalizedPath = path.Trim().Trim('"');
-        try
-        {
-            if (File.Exists(normalizedPath))
-            {
-                Process.Start("explorer.exe", $"/select,\"{normalizedPath}\"");
-            }
-            else if (Directory.Exists(normalizedPath))
-            {
-                Process.Start(new ProcessStartInfo { FileName = normalizedPath, UseShellExecute = true });
-            }
-        }
-        catch
-        {
-            // Ignore failures when opening Explorer.
-        }
-    }
 }