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/Services/UserAccessAuditService.cs

@@ -29,7 +29,8 @@ public class UserAccessAuditService : IUserAccessAuditService
         IReadOnlyList<SiteInfo> sites,
         ScanOptions options,
         IProgress<OperationProgress> progress,
-        CancellationToken ct)
+        CancellationToken ct,
+        Func<string, CancellationToken, Task<bool>>? onAccessDenied = null)
     {
         // Normalize target logins for case-insensitive matching.
         // Users may be identified by email ("alice@contoso.com") or full claim
@@ -59,10 +60,21 @@ public class UserAccessAuditService : IUserAccessAuditService
             };
 
             var ctx = await sessionManager.GetOrCreateContextAsync(profile, ct);
-            var permEntries = await _permissionsService.ScanSiteAsync(ctx, options, progress, ct);
+            IReadOnlyList<PermissionEntry> permEntries;
+            try
+            {
+                permEntries = await _permissionsService.ScanSiteAsync(ctx, options, progress, ct);
+            }
+            catch (Microsoft.SharePoint.Client.ServerUnauthorizedAccessException) when (onAccessDenied != null)
+            {
+                var elevated = await onAccessDenied(site.Url, ct);
+                if (!elevated)
+                    throw;
+                var retryCtx = await sessionManager.GetOrCreateContextAsync(profile, ct);
+                permEntries = await _permissionsService.ScanSiteAsync(retryCtx, options, progress, ct);
+            }
 
-            var userEntries = TransformEntries(permEntries, targets, site);
-            allEntries.AddRange(userEntries);
+            allEntries.AddRange(TransformEntries(permEntries, targets, site));
         }
 
         progress.Report(new OperationProgress(sites.Count, sites.Count,