Revert "[core] add optional status_code to error events (#6865)" (#6955)

This reverts commit c2ec477d93.

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codex-rs/exec/src/event_processor_with_human_output.rs

@@ -161,7 +161,7 @@ impl EventProcessor for EventProcessorWithHumanOutput {
     fn process_event(&mut self, event: Event) -> CodexStatus {
         let Event { id: _, msg } = event;
         match msg {
-            EventMsg::Error(ErrorEvent { message, .. }) => {
+            EventMsg::Error(ErrorEvent { message }) => {
                 let prefix = "ERROR:".style(self.red);
                 ts_msg!(self, "{prefix} {message}");
             }
@@ -221,7 +221,7 @@ impl EventProcessor for EventProcessorWithHumanOutput {
             EventMsg::BackgroundEvent(BackgroundEventEvent { message }) => {
                 ts_msg!(self, "{}", message.style(self.dimmed));
             }
-            EventMsg::StreamError(StreamErrorEvent { message, .. }) => {
+            EventMsg::StreamError(StreamErrorEvent { message }) => {
                 ts_msg!(self, "{}", message.style(self.dimmed));
             }
             EventMsg::TaskStarted(_) => {

codex-rs/exec/tests/event_processor_with_json_output.rs

@@ -539,7 +539,6 @@ fn error_event_produces_error() {
         "e1",
         EventMsg::Error(codex_core::protocol::ErrorEvent {
             message: "boom".to_string(),
-            http_status_code: Some(500),
         }),
     ));
     assert_eq!(
@@ -579,7 +578,6 @@ fn stream_error_event_produces_error() {
         "e1",
         EventMsg::StreamError(codex_core::protocol::StreamErrorEvent {
             message: "retrying".to_string(),
-            http_status_code: Some(500),
         }),
     ));
     assert_eq!(
@@ -598,7 +596,6 @@ fn error_followed_by_task_complete_produces_turn_failed() {
         "e1",
         EventMsg::Error(ErrorEvent {
             message: "boom".to_string(),
-            http_status_code: Some(500),
         }),
     );
     assert_eq!(