Alias tui.whimsy to tui.effects.starfield (#47908)

Normalize the legacy setting so existing `tui.whimsy` values control the
starfield effect. If both keys appear in the same config layer, the explicit
`tui.effects.starfield` value takes precedence.

GitOrigin-RevId: 2884dbd643690d500ed8d1493ce47950d93d6ab3

codex-rs/config/src/key_aliases.rs

@@ -10,6 +10,10 @@ struct ConfigKeyAlias {
 }
 
 const CONFIG_KEY_ALIASES: &[ConfigKeyAlias] = &[
+    ConfigKeyAlias {
+        legacy: &["tui", "whimsy"],
+        canonical: &["tui", "effects", "starfield"],
+    },
     ConfigKeyAlias {
         legacy: &["memories", "no_memories_if_mcp_or_web_search"],
         canonical: &["memories", "disable_on_external_context"],

codex-rs/tui/src/local_settings_tests.rs

@@ -97,7 +97,6 @@ async fn local_load_preserves_defaults_and_resolved_overrides() -> anyhow::Resul
         r#"
 [tui]
 animations = false
-whimsy = false # Retired: must not override effects or prevent strict loading.
 show_tooltips = false
 show_server_version_notice = false
 auto_recap = false