codex: rename rollout request id field

Rename the response stream field that carries an early request ID for rollout persistence so its purpose is explicit.

Co-authored-by: Codex <noreply@openai.com>

codex-rs/codex-api/src/common.rs

@@ -249,7 +249,7 @@ pub fn create_text_param_for_request(
 
 pub struct ResponseStream {
     pub rx_event: mpsc::Receiver<Result<ResponseEvent, ApiError>>,
-    pub initial_request_id: Option<String>,
+    pub rollout_request_id: Option<String>,
 }
 
 impl Stream for ResponseStream {

codex-rs/codex-api/src/endpoint/responses_websocket.rs

@@ -271,7 +271,7 @@ impl ResponsesWebsocketConnection {
             // Websocket upgrade response headers are scoped to the connection, not
             // individual `stream_request` calls, so they cannot be used as per-turn
             // request IDs in rollout metadata.
-            initial_request_id: None,
+            rollout_request_id: None,
         })
     }
 }

codex-rs/codex-api/src/sse/responses.rs

@@ -49,7 +49,7 @@ pub fn stream_from_fixture(
     tokio::spawn(process_sse(Box::pin(stream), tx_event, idle_timeout, None));
     Ok(ResponseStream {
         rx_event,
-        initial_request_id: None,
+        rollout_request_id: None,
     })
 }
 
@@ -104,7 +104,7 @@ pub fn spawn_response_stream(
 
     ResponseStream {
         rx_event,
-        initial_request_id: request_id,
+        rollout_request_id: request_id,
     }
 }
 
@@ -895,7 +895,7 @@ mod tests {
         };
 
         let stream = spawn_response_stream(stream_response, idle_timeout(), None, None);
-        assert_eq!(stream.initial_request_id.as_deref(), Some("req_123"));
+        assert_eq!(stream.rollout_request_id.as_deref(), Some("req_123"));
     }
 
     #[tokio::test]