feat: add bot_id and model to langfuse metadata

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

agent/agent_config.py

@@ -246,6 +246,10 @@ class AgentConfig:
                 langfuse_metadata["langfuse_session_id"] = self.session_id
             if self.user_identifier:
                 langfuse_metadata["langfuse_user_id"] = self.user_identifier
+            if self.bot_id:
+                langfuse_metadata["bot_id"] = self.bot_id
+            if self.model_name:
+                langfuse_metadata["model"] = self.model_name
 
         if callbacks:
             config["callbacks"] = callbacks