feat: expose type through the toc

src/Docfx.DataContracts.Common/TocItemViewModel.cs

@@ -92,6 +92,11 @@ public class TocItemViewModel
     [JsonPropertyName("order")]
     public int? Order { get; set; }
 
+    [YamlMember(Alias = Constants.PropertyName.Type)]
+    [JsonProperty(Constants.PropertyName.Type)]
+    [JsonPropertyName(Constants.PropertyName.Type)]
+    public string Type { get; set; }
+
     [YamlIgnore]
     [Newtonsoft.Json.JsonIgnore]
     [System.Text.Json.Serialization.JsonIgnore]

src/Docfx.Dotnet/YamlViewModelExtensions.cs

@@ -134,6 +134,7 @@ public static TocItemViewModel ToTocItemViewModel(this MetadataItem item, string
         {
             Uid = item.Name,
             Name = item.DisplayNames.GetLanguageProperty(SyntaxLanguage.Default),
+            Type = item.Type.ToString(),
         };
 
         if (item.Type is MemberType.Namespace)