feat: gpt5 params (#275)

* Update dispatcher.lua

Somehow GPT-5 does not supports temperature and max token parameter in api

* gpt-5

* Update dispatcher.lua

---------

Co-authored-by: Kyu Yeon Lee <rebel1324@gmail.com>

Author: Robitx

lua/gp/dispatcher.lua

@@ -190,6 +190,13 @@ D.prepare_payload = function(messages, model, provider)
 		output.top_p = nil
 	end
 
+	if model.model == "gpt-5" or  model.model == "gpt-5-mini" then
+		-- remove max_tokens, top_p, temperature for gpt-5 models (duh)
+		output.max_tokens = nil
+		output.temperature = nil
+		output.top_p = nil
+	end
+
 	return output
 end