Fix enum serialization (#61)

* Fix enum serialization

* Add tests for enum serialization

* Add missing enum serialization configuration.

* Ensure enums serialize as expected using defaults

---------

Co-authored-by: Eirik Tsarpalis <eirik.tsarpalis@gmail.com>

src/ModelContextProtocol/Client/McpClientExtensions.cs

@@ -485,7 +485,7 @@ public static class McpClientExtensions
         Throw.IfNull(client);
 
         return client.SendRequestAsync<EmptyResult>(
-            CreateRequest("logging/setLevel", new() { ["level"] = level.ToJsonValue() }),
+            CreateRequest("logging/setLevel", new() { ["level"] = level }),
             cancellationToken);
     }
 
@@ -514,22 +514,6 @@ public static class McpClientExtensions
         return parameters;
     }
 
-    private static string ToJsonValue(this LoggingLevel level)
-    {
-        return level switch
-        {
-            LoggingLevel.Debug => "debug",
-            LoggingLevel.Info => "info",
-            LoggingLevel.Notice => "notice",
-            LoggingLevel.Warning => "warning",
-            LoggingLevel.Error => "error",
-            LoggingLevel.Critical => "critical",
-            LoggingLevel.Alert => "alert",
-            LoggingLevel.Emergency => "emergency",
-            _ => throw new ArgumentOutOfRangeException(nameof(level))
-        };
-    }
-
     /// <summary>Provides an AI function that calls a tool through <see cref="IMcpClient"/>.</summary>
     private sealed class McpAIFunction(IMcpClient client, Tool tool) : AIFunction
     {