rework to isolate core

codex-rs/core/tests/suite/client_websockets.rs

@@ -1470,6 +1470,7 @@ fn message_item(text: &str) -> ResponseItem {
         id: None,
         role: "user".into(),
         content: vec![ContentItem::InputText { text: text.into() }],
+        metadata: None,
         end_turn: None,
         phase: None,
     }
@@ -1480,6 +1481,7 @@ fn assistant_message_item(id: &str, text: &str) -> ResponseItem {
         id: Some(id.to_string()),
         role: "assistant".into(),
         content: vec![ContentItem::OutputText { text: text.into() }],
+        metadata: None,
         end_turn: None,
         phase: None,
     }