tui: reject unavailable queued slash drafts on replay

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

codex-rs/tui/src/chatwidget.rs

@@ -5800,8 +5800,11 @@ impl ChatWidget {
         Some((cmd, rest, rest_offset))
     }
 
-    fn is_builtin_slash_draft(&self, draft: &UserMessage) -> bool {
-        self.parse_builtin_slash_command(&draft.text).is_some()
+    fn is_known_slash_draft(&self, draft: &UserMessage) -> bool {
+        let Some((name, _, _)) = parse_slash_name(&draft.text) else {
+            return false;
+        };
+        !name.contains('/') && SlashCommand::from_str(name).is_ok()
     }
 
     fn reject_unavailable_builtin_slash_command(&mut self, user_message: &UserMessage) -> bool {
@@ -6909,7 +6912,7 @@ impl ChatWidget {
             let Some(queued_message) = self.queued_user_messages.pop_front() else {
                 break;
             };
-            let replay_control = if self.is_builtin_slash_draft(&queued_message) {
+            let replay_control = if self.is_known_slash_draft(&queued_message) {
                 self.execute_serialized_slash_command(queued_message)
             } else {
                 self.submit_user_message(queued_message);

codex-rs/tui/src/chatwidget/tests.rs

@@ -8909,6 +8909,28 @@ async fn serialized_disabled_fast_slash_draft_is_rejected_immediately() {
     );
 }
 
+#[tokio::test]
+async fn queued_disabled_fast_slash_draft_is_rejected_on_replay() {
+    let (mut chat, mut rx, mut op_rx) = make_chatwidget_manual(Some("gpt-5.3-codex")).await;
+    chat.thread_id = Some(ThreadId::new());
+    chat.set_feature_enabled(Feature::FastMode, false);
+    chat.on_task_started();
+    chat.queued_user_messages.push_back("/fast on".into());
+
+    chat.bottom_pane.set_task_running(false);
+    chat.drain_queued_inputs_until_blocked();
+
+    assert_no_submit_op(&mut op_rx);
+    assert!(chat.queued_user_messages.is_empty());
+    assert_eq!(chat.bottom_pane.composer_text(), "/fast on");
+
+    let inserted = drain_insert_history(&mut rx);
+    assert_eq!(inserted.len(), 1);
+    assert!(
+        lines_to_single_string(&inserted[0]).contains("/fast is not available in this session.")
+    );
+}
+
 #[tokio::test]
 async fn user_turn_carries_service_tier_after_fast_toggle() {
     let (mut chat, mut rx, mut op_rx) = make_chatwidget_manual(Some("gpt-5.3-codex")).await;