Merge branch 'maintenance/ViewModels-defaults' into develop

Previously, some view model defaults were set on both the property's auto-value, as well as the `AttributeDictionary` constructor. This ensures that the constructor instead falls back to the auto-value. While this isn't strictly required, it helps avoid scenarios where the default value is updated in one place, but accidentally overlooked in the other.

Author: JeremyCaney

OnTopic.ViewModels/TopicViewModel.cs

@@ -29,7 +29,7 @@ public record TopicViewModel: ITopicViewModel, ICoreTopicViewModel, IAssociatedT
     /// <param name="attributes">An <see cref="AttributeDictionary"/> of attribute values.</param>
     public TopicViewModel(AttributeDictionary attributes) {
       Contract.Requires(attributes, nameof(attributes));
-      IsHidden                  = attributes.GetBoolean("IsHidden")?? false;
+      IsHidden                  = attributes.GetBoolean("IsHidden")?? IsHidden;
       View                      = attributes.GetValue("View");
     }
 

OnTopic.ViewModels/_contentTypes/ContentListTopicViewModel.cs

@@ -28,8 +28,8 @@ public record ContentListTopicViewModel: PageTopicViewModel {
     /// <param name="attributes">An <see cref="AttributeDictionary"/> of attribute values.</param>
     public ContentListTopicViewModel(AttributeDictionary attributes): base(attributes) {
       Contract.Requires(attributes, nameof(attributes));
-      IsIndexed                 = attributes.GetBoolean(nameof(IsIndexed))?? false;
-      IndexLabel                = attributes.GetValue(nameof(IndexLabel))?? "Contents";
+      IsIndexed                 = attributes.GetBoolean(nameof(IsIndexed))?? IsIndexed;
+      IndexLabel                = attributes.GetValue(nameof(IndexLabel))?? IndexLabel;
     }
 
     /// <summary>

OnTopic.ViewModels/_contentTypes/PageTopicViewModel.cs

@@ -33,7 +33,7 @@ public PageTopicViewModel(AttributeDictionary attributes): base(attributes) {
       MetaTitle                 = attributes.GetValue(nameof(MetaTitle));
       MetaDescription           = attributes.GetValue(nameof(MetaDescription));
       MetaKeywords              = attributes.GetValue(nameof(MetaKeywords));
-      NoIndex                   = attributes.GetBoolean(nameof(NoIndex))?? false;
+      NoIndex                   = attributes.GetBoolean(nameof(NoIndex))?? NoIndex;
       Body                      = attributes.GetValue(nameof(Body));
     }