[feat:] added "new file" button for wiki and therefore

implemented the usage of NamingWindow

MainWindow.axaml.cs

@@ -15,11 +15,11 @@ public partial class MainWindow : Window
     public static MainWindow _instance;
 
     private Country _selectedCountry;
+    private string _selectedWikiFilePath;
     private bool _suppressCountryRefresh;
 
     private WikiService _wikiService;
     public Uri filePath;
-    private string _selectedWikiFilePath;
 
     public MainWindow()
     {
@@ -872,4 +872,19 @@ public partial class MainWindow : Window
                 new List<string> { countryie.ThreeLetterCode, countryie.TwoLetterCode }));
         RefreshCountryView();
     }
+
+    private async void BtnWikiAddFile_OnClick(object? sender, RoutedEventArgs e)
+    {
+        var result = await NamingWindow.Show(this);
+        if (result != null)
+            try
+            {
+                File.WriteAllText(Path.Combine(Global._instance.wiki_storage_path, result), "");
+                PopulateNavTree();
+            }
+            catch (Exception ex)
+            {
+                MessageBox.Show(this, ex.StackTrace, "Fehler");
+            }
+    }
 }