Core Protocol docs edit pass (#1032)

src/ModelContextProtocol.Core/Protocol/Reference.cs

@@ -30,9 +30,9 @@ public abstract class Reference
     /// <summary>
     /// When overridden in a derived class, gets the type of content.
     /// </summary>
-    /// <remarks>
-    /// This can be "ref/resource" or "ref/prompt".
-    /// </remarks>
+    /// <value>
+    /// "ref/resource" or "ref/prompt".
+    /// </value>
     [JsonPropertyName("type")]
     public abstract string Type { get; }
 
@@ -192,4 +192,4 @@ public sealed class ResourceTemplateReference : Reference
 
     /// <inheritdoc />
     public override string ToString() => $"\"{Type}\": \"{Uri}\"";
-}
+}