feat(ui): add sender name display options

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

HellionChat/Ui/ChatLogWindow.cs

@@ -3076,6 +3076,14 @@ public sealed class ChatLogWindow : Window
         float lineWidth = 0f
     )
     {
+        // UI-7: render a copy with the sender name reformatted per the user's
+        // display options. Skipped in screenshot mode so the name-anonymising
+        // path in DrawChunk stays reliable (privacy wins). ForDisplay returns
+        // the list unchanged when nothing applies, so non-sender lists and the
+        // neutral default cost only a quick scan.
+        if (!ScreenshotMode)
+            chunks = SenderNameDisplay.ForDisplay(chunks);
+
         using var style = ImRaii.PushStyle(ImGuiStyleVar.ItemSpacing, Vector2.Zero);
 
         for (var i = 0; i < chunks.Count; i++)