tui: Allow extra o's in /goal command (#27814)

## Why

The TUI rejected playful `/goal` spellings such as `/goooooooooooal`,
even though Codex Apps accepts them for the World Cup promotion. This
keeps the TUI behavior consistent without changing how the canonical
command is presented.

## How it works

Built-in command lookup recognizes lowercase `go+al` as the existing
`goal` command after normal exact-name parsing fails. The command
catalog remains unchanged, so autocomplete continues to advertise
`/goal` normally.

## Verification

Added lookup-level and end-to-end TUI coverage for the flexible
spelling. The focused tests, scoped Clippy checks, and formatting pass.
The full `codex-tui` suite passed 2,833 of 2,835 tests; the two failing
guardian feature-flag tests reproduce unchanged on fresh `origin/main`.

codex-rs/tui/src/bottom_pane/slash_commands.rs

@@ -106,12 +106,16 @@ pub(crate) fn commands_for_input(
         .collect()
 }
 
-/// Find a single built-in command by exact name, after applying feature gating.
+/// Find a single built-in command by a recognized name or alias, after applying feature gating.
 ///
-/// Side-conversation gating is intentionally enforced by dispatch rather than exact lookup so a
+/// Side-conversation gating is intentionally enforced by dispatch rather than command lookup so a
 /// typed command can produce a side-specific unavailable message while the popup still hides it.
 pub(crate) fn find_builtin_command(name: &str, flags: BuiltinCommandFlags) -> Option<SlashCommand> {
-    let cmd = SlashCommand::from_str(name).ok()?;
+    let cmd = SlashCommand::from_str(name).ok().or_else(|| {
+        let repeated_os = name.strip_prefix('g')?.strip_suffix("al")?;
+        (!repeated_os.is_empty() && repeated_os.bytes().all(|byte| byte == b'o'))
+            .then_some(SlashCommand::Goal)
+    })?;
     builtins_for_input(BuiltinCommandFlags {
         side_conversation_active: false,
         ..flags
@@ -187,6 +191,14 @@ mod tests {
         );
     }
 
+    #[test]
+    fn goal_command_allows_extra_os_for_dispatch() {
+        assert_eq!(
+            find_builtin_command("goooooooooooal", all_enabled_flags()),
+            Some(SlashCommand::Goal)
+        );
+    }
+
     #[test]
     fn stop_command_resolves_for_dispatch() {
         assert_eq!(

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

@@ -599,12 +599,12 @@ async fn inline_slash_command_is_available_from_local_recall_after_dispatch() {
 }
 
 #[tokio::test]
-async fn goal_slash_command_emits_set_goal_event() {
+async fn goal_slash_command_with_extra_os_emits_set_goal_event() {
     let (mut chat, mut rx, mut op_rx) = make_chatwidget_manual(/*model_override*/ None).await;
     chat.set_feature_enabled(Feature::Goals, /*enabled*/ true);
     let thread_id = ThreadId::new();
     chat.thread_id = Some(thread_id);
-    let command = "/goal --tokens 98.5K improve benchmark coverage";
+    let command = "/goooooooooooal --tokens 98.5K improve benchmark coverage";
 
     submit_composer_text(&mut chat, command);