feat:First version of Gemini chat evaluator class.

lib/LLM/Functions/EvaluatorChatGemini.rakumod

@@ -0,0 +1,21 @@
+use LLM::Functions::EvaluatorChat;
+
+# Should this class inherit from Evaluator or from EvaluatorChat
+class LLM::Functions::EvaluatorChatGemini
+        is LLM::Functions::EvaluatorChat {
+
+    submethod TWEAK {
+        self.assitant-role = 'model';
+        self.system-role = 'user';
+    }
+
+    method prompt-texts-combiner($prompt, @texts, *%args) {
+        my @messages = self.LLM::Functions::EvaluatorChat::prompt-texts-combiner($prompt, @texts, |%args);
+
+        if @messages.elems ≥ 2 && @messages[0].key eq @messages[1].key eq self.system-role {
+            @messages = [@messages.head, Pair.new(self.assitant-role, "OK."), @messages.tail(*-1)];
+        }
+
+        return @messages;
+    }
+}