feat(07-07): add UserAccessAuditTabItem to MainWindow and wire dialog factory

- Add UserAccessAuditTabItem to MainWindow.xaml TabControl before SettingsTabItem
- Wire UserAccessAuditView content and SitePickerDialog factory in MainWindow.xaml.cs

SharepointToolbox/MainWindow.xaml.cs

@@ -47,6 +47,20 @@ public partial class MainWindow : Window
         FolderStructureTabItem.Content = serviceProvider.GetRequiredService<FolderStructureView>();
         TemplatesTabItem.Content = serviceProvider.GetRequiredService<TemplatesView>();
 
+        // Phase 7: User Access Audit
+        var auditView = serviceProvider.GetRequiredService<UserAccessAuditView>();
+        UserAccessAuditTabItem.Content = auditView;
+
+        // Wire site picker dialog factory for audit tab (same pattern as PermissionsView)
+        if (auditView.DataContext is ViewModels.Tabs.UserAccessAuditViewModel auditVm)
+        {
+            auditVm.OpenSitePickerDialog = () =>
+            {
+                var factory = serviceProvider.GetRequiredService<Func<TenantProfile, SitePickerDialog>>();
+                return factory(auditVm.CurrentProfile ?? new TenantProfile());
+            };
+        }
+
         // Replace Settings tab placeholder with the DI-resolved SettingsView
         SettingsTabItem.Content = serviceProvider.GetRequiredService<SettingsView>();