Suppress errors for requested session stops

server/src/session/codex.rs

@@ -623,6 +623,7 @@ async fn follow(inner: Arc<Inner>, mut record: process::Record, mut offset: u64)
             process::Liveness::Alive | process::Liveness::Unknown => {}
             process::Liveness::Dead if complete > 0 => {}
             process::Liveness::Dead => {
+                let stopped = process::stopping(&inner.session_dir);
                 process::clear(&inner.session_dir);
                 let dropped = {
                     let mut state = inner.state.lock().unwrap();
@@ -639,11 +640,13 @@ async fn follow(inner: Arc<Inner>, mut record: process::Record, mut offset: u64)
                 for id in dropped {
                     let _ = inner.sink.send(Event::MessageDropped { id });
                 }
-                let detail = stderr_tail(&stderr);
-                if !detail.is_empty() {
-                    let _ = inner.sink.send(Event::Error {
-                        message: format!("Codex exited:\n{detail}"),
-                    });
+                if !stopped {
+                    let detail = stderr_tail(&stderr);
+                    if !detail.is_empty() {
+                        let _ = inner.sink.send(Event::Error {
+                            message: format!("Codex exited:\n{detail}"),
+                        });
+                    }
                 }
                 let _ = inner.sink.send(Event::Status {
                     state: SessionStatus::Exited,