add: Added support for any openai compatible api for the chatterbot feature

change: Changed games.yml to allow input of the apiUrl (needs to be openai compatible) and modelName as a string.

src/NadekoBot/Modules/Games/ChatterBot/_common/OpenAiApi/OpenAiApiMessage.cs

@@ -0,0 +1,15 @@
+using System.Text.Json.Serialization;
+
+namespace NadekoBot.Modules.Games.Common.ChatterBot;
+
+public class OpenAiApiMessage
+{
+    [JsonPropertyName("role")]
+    public string Role { get; init; }
+
+    [JsonPropertyName("content")]
+    public string Content { get; init; }
+
+    [JsonPropertyName("name")]
+    public string Name { get; init; }
+}