chore: release v2.4

- Add theme system (Dark/Light palettes, ModernTheme, ThemeManager)
- Add InputDialog, Spinner common view
- Add DuplicatesCsvExportService
- Refresh views, dialogs, and view models across tabs
- Update localization strings (en/fr)
- Tweak services (transfer, permissions, search, user access, ownership elevation, bulk operations)

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

SharepointToolbox/ViewModels/Tabs/UserAccessAuditViewModel.cs

@@ -27,6 +27,8 @@ public partial class UserAccessAuditViewModel : FeatureViewModelBase
     private readonly UserAccessHtmlExportService? _htmlExportService;
     private readonly IBrandingService? _brandingService;
     private readonly IGraphUserDirectoryService? _graphUserDirectoryService;
+    private readonly IOwnershipElevationService? _ownershipService;
+    private readonly SettingsService? _settingsService;
     private readonly ILogger<FeatureViewModelBase> _logger;
 
     // ── People picker debounce ──────────────────────────────────────────────
@@ -163,7 +165,9 @@ public partial class UserAccessAuditViewModel : FeatureViewModelBase
         UserAccessHtmlExportService htmlExportService,
         IBrandingService brandingService,
         IGraphUserDirectoryService graphUserDirectoryService,
-        ILogger<FeatureViewModelBase> logger)
+        ILogger<FeatureViewModelBase> logger,
+        IOwnershipElevationService? ownershipService = null,
+        SettingsService? settingsService = null)
         : base(logger)
     {
         _auditService = auditService;
@@ -173,6 +177,8 @@ public partial class UserAccessAuditViewModel : FeatureViewModelBase
         _htmlExportService = htmlExportService;
         _brandingService = brandingService;
         _graphUserDirectoryService = graphUserDirectoryService;
+        _ownershipService = ownershipService;
+        _settingsService = settingsService;
         _logger = logger;
 
         ExportCsvCommand = new AsyncRelayCommand(ExportCsvAsync, CanExport);
@@ -273,6 +279,35 @@ public partial class UserAccessAuditViewModel : FeatureViewModelBase
             return;
         }
 
+        var autoOwnership = await IsAutoTakeOwnershipEnabled();
+
+        Func<string, CancellationToken, Task<bool>>? onAccessDenied = null;
+        if (_ownershipService != null && autoOwnership)
+        {
+            onAccessDenied = async (siteUrl, token) =>
+            {
+                try
+                {
+                    _logger.LogWarning("Access denied on {Url}, auto-elevating ownership...", siteUrl);
+                    var adminUrl = DeriveAdminUrl(_currentProfile?.TenantUrl ?? siteUrl);
+                    var adminProfile = new TenantProfile
+                    {
+                        TenantUrl = adminUrl,
+                        ClientId = _currentProfile?.ClientId ?? string.Empty,
+                        Name = _currentProfile?.Name ?? string.Empty
+                    };
+                    var adminCtx = await _sessionManager.GetOrCreateContextAsync(adminProfile, token);
+                    await _ownershipService.ElevateAsync(adminCtx, siteUrl, string.Empty, token);
+                    return true;
+                }
+                catch (Exception ex)
+                {
+                    _logger.LogError(ex, "Auto-elevation failed for {Url}", siteUrl);
+                    return false;
+                }
+            };
+        }
+
         var entries = await _auditService.AuditUsersAsync(
             _sessionManager,
             _currentProfile,
@@ -280,7 +315,8 @@ public partial class UserAccessAuditViewModel : FeatureViewModelBase
             effectiveSites,
             scanOptions,
             progress,
-            ct);
+            ct,
+            onAccessDenied);
 
         // Update Results on the UI thread — clear + repopulate (not replace)
         // so the CollectionViewSource bound to ResultsView stays connected.
@@ -307,6 +343,26 @@ public partial class UserAccessAuditViewModel : FeatureViewModelBase
         ExportHtmlCommand.NotifyCanExecuteChanged();
     }
 
+    // ── Auto-ownership helpers ───────────────────────────────────────────────
+
+    private async Task<bool> IsAutoTakeOwnershipEnabled()
+    {
+        if (_settingsService == null) return false;
+        var settings = await _settingsService.GetSettingsAsync();
+        return settings.AutoTakeOwnership;
+    }
+
+    internal static string DeriveAdminUrl(string tenantUrl)
+    {
+        var uri = new Uri(tenantUrl.TrimEnd('/'));
+        var host = uri.Host;
+        if (host.Contains("-admin.sharepoint.com", StringComparison.OrdinalIgnoreCase))
+            return tenantUrl;
+        var adminHost = host.Replace(".sharepoint.com", "-admin.sharepoint.com",
+            StringComparison.OrdinalIgnoreCase);
+        return $"{uri.Scheme}://{adminHost}";
+    }
+
     // ── Tenant switching ─────────────────────────────────────────────────────
 
     protected override void OnTenantSwitched(TenantProfile profile)