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/Export/CsvExportService.cs

@@ -1,6 +1,7 @@
 using System.IO;
 using System.Text;
 using SharepointToolbox.Core.Models;
+using SharepointToolbox.Localization;
 
 namespace SharepointToolbox.Services.Export;
 
@@ -10,8 +11,11 @@ namespace SharepointToolbox.Services.Export;
 /// </summary>
 public class CsvExportService
 {
-    private const string Header =
-        "\"Object\",\"Title\",\"URL\",\"HasUniquePermissions\",\"Users\",\"UserLogins\",\"Type\",\"Permissions\",\"GrantedThrough\"";
+    private static string BuildHeader()
+    {
+        var T = TranslationSource.Instance;
+        return $"\"{T["report.col.object"]}\",\"{T["report.col.title"]}\",\"{T["report.col.url"]}\",\"HasUniquePermissions\",\"Users\",\"UserLogins\",\"Type\",\"Permissions\",\"GrantedThrough\"";
+    }
 
     /// <summary>
     /// Builds a CSV string from the supplied permission entries.
@@ -20,7 +24,7 @@ public class CsvExportService
     public string BuildCsv(IReadOnlyList<PermissionEntry> entries)
     {
         var sb = new StringBuilder();
-        sb.AppendLine(Header);
+        sb.AppendLine(BuildHeader());
 
         // Merge: group by (Users, PermissionLevels, GrantedThrough) — port of PS Merge-PermissionRows
         var merged = entries
@@ -61,8 +65,11 @@ public class CsvExportService
     /// <summary>
     /// Header for simplified CSV export — includes "SimplifiedLabels" and "RiskLevel" columns.
     /// </summary>
-    private const string SimplifiedHeader =
-        "\"Object\",\"Title\",\"URL\",\"HasUniquePermissions\",\"Users\",\"UserLogins\",\"Type\",\"Permissions\",\"SimplifiedLabels\",\"RiskLevel\",\"GrantedThrough\"";
+    private static string BuildSimplifiedHeader()
+    {
+        var T = TranslationSource.Instance;
+        return $"\"{T["report.col.object"]}\",\"{T["report.col.title"]}\",\"{T["report.col.url"]}\",\"HasUniquePermissions\",\"Users\",\"UserLogins\",\"Type\",\"Permissions\",\"SimplifiedLabels\",\"RiskLevel\",\"GrantedThrough\"";
+    }
 
     /// <summary>
     /// Builds a CSV string from simplified permission entries.
@@ -72,7 +79,7 @@ public class CsvExportService
     public string BuildCsv(IReadOnlyList<SimplifiedPermissionEntry> entries)
     {
         var sb = new StringBuilder();
-        sb.AppendLine(SimplifiedHeader);
+        sb.AppendLine(BuildSimplifiedHeader());
 
         var merged = entries
             .GroupBy(e => (e.Users, e.PermissionLevels, e.GrantedThrough))