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/DuplicatesService.cs

@@ -1,7 +1,9 @@
+using System.Diagnostics;
 using Microsoft.SharePoint.Client;
 using Microsoft.SharePoint.Client.Search.Query;
 using SharepointToolbox.Core.Helpers;
 using SharepointToolbox.Core.Models;
+using SharepointToolbox.Services.Export;
 
 namespace SharepointToolbox.Services;
 
@@ -13,9 +15,27 @@ namespace SharepointToolbox.Services;
 /// </summary>
 public class DuplicatesService : IDuplicatesService
 {
+    // SharePoint Search REST API caps RowLimit at 500 per request; larger values are silently clamped.
     private const int BatchSize = 500;
+
+    // SharePoint Search hard ceiling — StartRow > 50,000 returns an error regardless of pagination state.
+    // See https://learn.microsoft.com/sharepoint/dev/general-development/customizing-search-results-in-sharepoint
     private const int MaxStartRow = 50_000;
 
+    /// <summary>
+    /// Scans a site for duplicate files or folders and groups matches by the
+    /// composite key configured in <paramref name="options"/> (name plus any
+    /// of size / created / modified / subfolder-count / file-count).
+    /// File mode uses the SharePoint Search API — it is fast but capped at
+    /// 50,000 rows (see <see cref="MaxStartRow"/>). Folder mode uses paginated
+    /// CSOM CAML over every document library on the site. Groups with fewer
+    /// than two items are dropped before return.
+    /// </summary>
+    /// <param name="ctx">Authenticated <see cref="ClientContext"/> for the target site.</param>
+    /// <param name="options">Scope (Files/Folders), optional library filter, and match-key toggles.</param>
+    /// <param name="progress">Receives row-count progress during collection.</param>
+    /// <param name="ct">Cancellation token — honoured between paged requests.</param>
+    /// <returns>Duplicate groups ordered by descending size, then name.</returns>
     public async Task<IReadOnlyList<DuplicateGroup>> ScanDuplicatesAsync(
         ClientContext ctx,
         DuplicateScanOptions options,
@@ -70,6 +90,8 @@ public class DuplicatesService : IDuplicatesService
         IProgress<OperationProgress> progress,
         CancellationToken ct)
     {
+        var (siteUrl, siteTitle) = await LoadSiteIdentityAsync(ctx, progress, ct);
+
         // KQL: all documents, optionally scoped to a library
         var kqlParts = new List<string> { "ContentType:Document" };
         if (!string.IsNullOrEmpty(options.Library))
@@ -102,10 +124,25 @@ public class DuplicatesService : IDuplicatesService
                 .FirstOrDefault(t => t.TableType == KnownTableTypes.RelevantResults);
             if (table == null || table.RowCount == 0) break;
 
-            foreach (System.Collections.Hashtable row in table.ResultRows)
+            foreach (var rawRow in table.ResultRows)
             {
-                var dict = row.Cast<System.Collections.DictionaryEntry>()
-                    .ToDictionary(e => e.Key.ToString()!, e => e.Value ?? (object)string.Empty);
+                // CSOM has returned ResultRows as either Hashtable or
+                // Dictionary<string,object> across versions — accept both.
+                IDictionary<string, object> dict;
+                if (rawRow is IDictionary<string, object> generic)
+                {
+                    dict = generic;
+                }
+                else if (rawRow is System.Collections.IDictionary legacy)
+                {
+                    dict = new Dictionary<string, object>();
+                    foreach (System.Collections.DictionaryEntry e in legacy)
+                        dict[e.Key.ToString()!] = e.Value ?? string.Empty;
+                }
+                else
+                {
+                    continue;
+                }
 
                 string path = GetStr(dict, "Path");
                 if (path.Contains("/_vti_history/", StringComparison.OrdinalIgnoreCase))
@@ -132,7 +169,9 @@ public class DuplicatesService : IDuplicatesService
                     Library   = library,
                     SizeBytes = size,
                     Created   = created,
-                    Modified  = modified
+                    Modified  = modified,
+                    SiteUrl   = siteUrl,
+                    SiteTitle = siteTitle
                 });
             }
 
@@ -156,10 +195,16 @@ public class DuplicatesService : IDuplicatesService
     {
         // Load all document libraries on the site
         ctx.Load(ctx.Web,
+            w => w.Title,
             w => w.Lists.Include(
                 l => l.Title, l => l.Hidden, l => l.BaseType));
         await ExecuteQueryRetryHelper.ExecuteQueryRetryAsync(ctx, progress, ct);
 
+        var siteUrl = ctx.Url;
+        var siteTitle = string.IsNullOrWhiteSpace(ctx.Web.Title)
+            ? ReportSplitHelper.DeriveSiteLabel(siteUrl)
+            : ctx.Web.Title;
+
         var libs = ctx.Web.Lists
             .Where(l => !l.Hidden && l.BaseType == BaseType.DocumentLibrary)
             .ToList();
@@ -172,19 +217,15 @@ public class DuplicatesService : IDuplicatesService
                 .ToList();
         }
 
+        // No WHERE clause — a WHERE on non-indexed fields (FSObjType) throws the
+        // list-view threshold on libraries > 5,000 items even with pagination.
+        // Filter for folders client-side via FileSystemObjectType below.
         var camlQuery = new CamlQuery
         {
             ViewXml = """
                 <View Scope='RecursiveAll'>
-                  <Query>
-                    <Where>
-                      <Eq>
-                        <FieldRef Name='FSObjType' />
-                        <Value Type='Integer'>1</Value>
-                      </Eq>
-                    </Where>
-                  </Query>
-                  <RowLimit>2000</RowLimit>
+                  <Query></Query>
+                  <RowLimit Paged='TRUE'>5000</RowLimit>
                 </View>
                 """
         };
@@ -200,6 +241,8 @@ public class DuplicatesService : IDuplicatesService
             {
                 ct.ThrowIfCancellationRequested();
 
+                if (item.FileSystemObjectType != FileSystemObjectType.Folder) continue;
+
                 var fv = item.FieldValues;
                 string name      = fv["FileLeafRef"]?.ToString() ?? string.Empty;
                 string fileRef   = fv["FileRef"]?.ToString() ?? string.Empty;
@@ -217,7 +260,9 @@ public class DuplicatesService : IDuplicatesService
                     FolderCount = subCount,
                     FileCount   = fileCount,
                     Created     = created,
-                    Modified    = modified
+                    Modified    = modified,
+                    SiteUrl     = siteUrl,
+                    SiteTitle   = siteTitle
                 });
             }
         }
@@ -246,6 +291,37 @@ public class DuplicatesService : IDuplicatesService
     private static DateTime? ParseDate(string s) =>
         DateTime.TryParse(s, out var dt) ? dt : (DateTime?)null;
 
+    private static async Task<(string Url, string Title)> LoadSiteIdentityAsync(
+        ClientContext ctx, IProgress<OperationProgress> progress, CancellationToken ct)
+    {
+        try
+        {
+            ctx.Load(ctx.Web, w => w.Title);
+            await ExecuteQueryRetryHelper.ExecuteQueryRetryAsync(ctx, progress, ct);
+        }
+        catch (OperationCanceledException)
+        {
+            throw;
+        }
+        catch (Exception ex)
+        {
+            // Best-effort — fall back to URL-derived label
+            Debug.WriteLine($"[DuplicatesService] LoadSiteIdentityAsync: failed to load Web.Title: {ex.GetType().Name}: {ex.Message}");
+        }
+
+        var url = ctx.Url ?? string.Empty;
+        string title;
+        try { title = ctx.Web.Title; }
+        catch (Exception ex)
+        {
+            Debug.WriteLine($"[DuplicatesService] LoadSiteIdentityAsync: Web.Title getter threw: {ex.GetType().Name}: {ex.Message}");
+            title = string.Empty;
+        }
+        if (string.IsNullOrWhiteSpace(title))
+            title = ReportSplitHelper.DeriveSiteLabel(url);
+        return (url, title);
+    }
+
     private static string ExtractLibraryFromPath(string path, string siteUrl)
     {
         // Extract first path segment after the site URL as library name