Fix navigation to use AboutFrame instead of parent Frame

The issue was that AboutPage was using NavigationService which navigated
in the parent TabControl Frame, not the AboutFrame we created. This caused:
- The default navigation UI to appear in the wrong place
- Our custom navigation buttons to remain disabled

Now AboutPage correctly navigates within its immediate parent Frame (AboutFrame),
ensuring the custom back/forward arrows work properly.

Author: cursoragent

src/Captura/Pages/AboutPage.xaml.cs

@@ -1,4 +1,5 @@
 using System.Windows;
+using System.Windows.Controls;
 using Captura.Views;
 
 namespace Captura
@@ -7,12 +8,30 @@ public partial class AboutPage
     {
         void ViewLicenses(object Sender, RoutedEventArgs E)
         {
-            NavigationService?.Navigate(new LicensesPage());
+            // Navigate using the immediate parent Frame (AboutFrame), not the grandparent
+            var parentFrame = Parent as Frame;
+            if (parentFrame != null)
+            {
+                parentFrame.Navigate(new LicensesPage());
+            }
+            else
+            {
+                NavigationService?.Navigate(new LicensesPage());
+            }
         }
 
         void ViewCrashLogs(object Sender, RoutedEventArgs E)
         {
-            NavigationService?.Navigate(new CrashLogsPage());
+            // Navigate using the immediate parent Frame (AboutFrame), not the grandparent
+            var parentFrame = Parent as Frame;
+            if (parentFrame != null)
+            {
+                parentFrame.Navigate(new CrashLogsPage());
+            }
+            else
+            {
+                NavigationService?.Navigate(new CrashLogsPage());
+            }
         }
     }
 }