add limits related to current messages to config

src/config_example.ts

@@ -31,4 +31,14 @@ export default class config {
     model: "gpt-3.5-turbo",
     max_tokens: 384,
   };
+
+  /** limits for message selection */
+  static readonly limits = {
+    /** maximum time in the past for messages (in miliseconds) */
+    time: 60*60*1000,
+    /** maximum number of messages to select (maximum 100) */
+    messages: 50,
+    /** maximum total token usage for messages */
+    tokens: 2048,
+  };
 }