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.Tests/ViewModels/FeatureViewModelBaseTests.cs

@@ -44,19 +44,25 @@ public class FeatureViewModelBaseTests
     public async Task ProgressValue_AndStatusMessage_UpdateViaIProgress()
     {
         var vm = new TestViewModel();
+        int midProgress = -1;
+        string? midStatus = null;
+
         vm.OperationFunc = async (ct, progress) =>
         {
             progress.Report(new OperationProgress(50, 100, "halfway"));
-            await Task.Yield();
+            // Let the Progress<T> callback dispatch before sampling.
+            await Task.Delay(20, ct);
+            midProgress = vm.ProgressValue;
+            midStatus   = vm.StatusMessage;
         };
 
         await vm.RunCommand.ExecuteAsync(null);
 
-        // Allow dispatcher to process
-        await Task.Delay(20);
-
-        Assert.Equal(50, vm.ProgressValue);
-        Assert.Equal("halfway", vm.StatusMessage);
+        // Mid-operation snapshot confirms IProgress reaches bound properties.
+        // Post-completion, FeatureViewModelBase snaps to 100% / "Complete"
+        // so stale "Scanning X" labels don't linger after a successful run.
+        Assert.Equal(50, midProgress);
+        Assert.Equal("halfway", midStatus);
     }
 
     [Fact]