Honor the tooltip preference for TUI startup help (#58127)

## Why

The startup command list was shown even when tooltips were disabled.

## What changed

Show the getting-started help only when `show_tooltips` is enabled. Keep regular tooltips and model-change notices suppressed on the first session event.

## Testing

Extend the first-event test to cover both tooltip preferences and update the startup header snapshot.

GitOrigin-RevId: 7b4a043737053f1a078cb21528dc459f0cfd762b

codex-rs/tui/src/chatwidget/snapshots/codex_tui__chatwidget__tests__catalog_model_session_header_startup.snap

@@ -6,11 +6,3 @@ expression: rendered
 OpenAI Codex (v<VERSION>)
 model: GPT-5.6 Luna high
 directory: /tmp/thread-settings
-
-  To get started, describe a task or try one of these commands:
-
-  /init - create an AGENTS.md file with instructions for Codex
-  /status - show current session configuration
-  /permissions - choose what Codex is allowed to do
-  /model - choose what model and reasoning effort to use
-  /review - review any changes and find issues

codex-rs/tui/src/history_cell/session.rs

@@ -213,7 +213,7 @@ pub(crate) fn new_session_info(
     ));
     let mut parts: Vec<Box<dyn HistoryCell>> = vec![Box::new(header)];
 
-    if is_first_event {
+    if is_first_event && local_settings.tui.show_tooltips {
         // Help lines below the header (new copy and list)
         let help_lines: Vec<Line<'static>> = vec![
             "  To get started, describe a task or try one of these commands:"
@@ -248,7 +248,7 @@ pub(crate) fn new_session_info(
         ];
 
         parts.push(Box::new(PlainHistoryCell { lines: help_lines }));
-    } else {
+    } else if !is_first_event {
         if local_settings.tui.show_tooltips
             && let Some(tooltips) = tooltip_override
                 .or_else(|| tooltips::get_tooltip(auth_plan, &local_settings.tui.keymap))

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

@@ -827,22 +827,27 @@ async fn session_info_preserves_styled_tooltip_links() {
 }
 
 #[tokio::test]
-async fn session_info_first_event_suppresses_tooltips_and_nux() {
+async fn session_info_first_event_respects_tooltip_preference() {
     let config = test_config().await;
-    let cell = new_session_info(
-        &config,
-        &crate::local_settings::LocalSettings::from(&config),
-        "gpt-5",
-        "gpt-5",
-        &session_configured_event("gpt-5"),
-        /*is_first_event*/ true,
-        Some("Model just became available".to_string()),
-        Some(PlanType::Free),
-    );
+    let mut local_settings = crate::local_settings::LocalSettings::from(&config);
+    for show_tooltips in [true, false] {
+        local_settings.tui.show_tooltips = show_tooltips;
+        let cell = new_session_info(
+            &config,
+            &local_settings,
+            "requested-model",
+            "gpt-5",
+            &session_configured_event("gpt-5"),
+            /*is_first_event*/ true,
+            Some("Model just became available".to_string()),
+            Some(PlanType::Free),
+        );
 
-    let rendered = render_transcript(&cell).join("\n");
-    assert!(!rendered.contains("Model just became available"));
-    assert!(rendered.contains("To get started"));
+        let rendered = render_transcript(&cell).join("\n");
+        assert_eq!(rendered.contains("To get started"), show_tooltips);
+        assert!(!rendered.contains("Model just became available"));
+        assert!(!rendered.contains("model changed:"));
+    }
 }
 
 #[tokio::test]