Fix single-message mode to exit after one turn when background channels are enabled (#719)

src/channels/repl.rs

@@ -303,6 +303,9 @@ impl Channel for ReplChannel {
             if let Some(msg) = single_message {
                 let incoming = IncomingMessage::new("repl", "default", &msg).with_timezone(&sys_tz);
                 let _ = tx.blocking_send(incoming);
+                // Ensure the agent exits after handling exactly one turn in -m mode,
+                // even when other channels (gateway/http) are enabled.
+                let _ = tx.blocking_send(IncomingMessage::new("repl", "default", "/quit"));
                 return;
             }
 
@@ -621,3 +624,29 @@ impl Channel for ReplChannel {
         Ok(())
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use futures::StreamExt;
+
+    use super::*;
+
+    #[tokio::test]
+    async fn single_message_mode_sends_message_then_quit() {
+        let repl = ReplChannel::with_message("hi".to_string());
+        let mut stream = repl.start().await.expect("repl start should succeed");
+
+        let first = stream.next().await.expect("first message missing");
+        assert_eq!(first.channel, "repl");
+        assert_eq!(first.content, "hi");
+
+        let second = stream.next().await.expect("quit message missing");
+        assert_eq!(second.channel, "repl");
+        assert_eq!(second.content, "/quit");
+
+        assert!(
+            stream.next().await.is_none(),
+            "stream should end after /quit"
+        );
+    }
+}