Adding Response Format - Correcting non-standard way of working with PromptExecutionSettings

can be used downstream to post-process the messages based on the requested format

LLama.SemanticKernel/LLamaSharpPromptExecutionSettings.cs

@@ -74,6 +74,12 @@ public class LLamaSharpPromptExecutionSettings : PromptExecutionSettings
     [JsonPropertyName("token_selection_biases")]
     public IDictionary<int, int> TokenSelectionBiases { get; set; } = new Dictionary<int, int>();
 
+    /// <summary>
+    /// Indicates the format of the response which can be used downstream to post-process the messages. Handlebars: handlebars_object. JSON: json_object, etc.
+    /// </summary>
+    [JsonPropertyName("response_format")]
+    public string ResponseFormat { get; set; } = string.Empty;
+
     /// <summary>
     /// Create a new settings object with the values from another settings object.
     /// </summary>