SF-74: Domain/Application — UserPreferences DTO, interface, Sender role constant

EnvelopeGenerator.Application/Common/Dto/UserPreferencesDto.cs

@@ -3,7 +3,7 @@ namespace EnvelopeGenerator.Application.Common.Dto;
 /// <summary>
 /// Represents a user's UI preferences stored in the distributed cache (dbo.TBDD_CACHE).
 /// </summary>
-public sealed class UserPreferencesDto
+public sealed record UserPreferencesDto
 {
     /// <summary>
     /// The active DevExpress theme name.
@@ -23,4 +23,17 @@ public sealed class UserPreferencesDto
     /// Values are opaque JSON strings produced by DxGrid.SaveLayoutAsync().
     /// </summary>
     public Dictionary<string, string> GridLayouts { get; set; } = new();
+
+    /// <summary>
+    /// The authenticated user's display name ("{GivenName} {Surname}").
+    /// Populated by the server on GET responses from JWT claims.
+    /// NOT persisted in cache — injected at read time by UserPreferencesController.
+    /// Ignored on PUT requests.
+    /// </summary>
+    public string? DisplayName { get; set; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public static UserPreferencesDto Default { get; } = new UserPreferencesDto();
 }