feat(client): add ToString to ApiEnum

Author: stainless-app[bot]

src/Orb/Core/ApiEnum.cs

@@ -94,6 +94,9 @@ public virtual bool Equals(ApiEnum<TRaw, TEnum>? other)
         return other != null && JsonElement.DeepEquals(this.Json, other.Json);
     }
 
+    public override string ToString() =>
+        JsonSerializer.Serialize(this.Json, ModelBase.ToStringSerializerOptions);
+
     public override int GetHashCode()
     {
         return 0;