feat(environment): add conversation history builder from last 5 attack turns

server/environment.py

@@ -62,4 +62,10 @@ class RedTeamEnvironment:
             raise ValueError("Episode already complete. Call /reset to start a new one.")
 
         self.turn += 1
+
+        # Last 5 turns as conversation context for the defender
+        conversation_history = [
+            {"role": "user", "content": h["framing"]}
+            for h in self.attack_history[-5:]
+        ]
         return None # Placeholder