test: include alternate_screen in tui default

Author: hjanuschka

codex-rs/core/src/config/mod.rs

@@ -1632,6 +1632,7 @@ persistence = "none"
                 scroll_wheel_tick_detect_max_ms: None,
                 scroll_wheel_like_max_duration_ms: None,
                 scroll_invert: false,
+                alternate_screen: AltScreenMode::Auto,
             }
         );
     }

codex-rs/protocol/src/config_types.rs

@@ -86,7 +86,9 @@ pub enum TrustLevel {
 /// Using alternate screen provides a cleaner fullscreen experience but prevents
 /// scrollback in terminal multiplexers like Zellij that follow the xterm spec
 /// (which says alternate screen should not have scrollback).
-#[derive(Debug, Serialize, Deserialize, Default, Clone, Copy, PartialEq, Eq, Display, JsonSchema, TS)]
+#[derive(
+    Debug, Serialize, Deserialize, Default, Clone, Copy, PartialEq, Eq, Display, JsonSchema, TS,
+)]
 #[serde(rename_all = "lowercase")]
 #[strum(serialize_all = "lowercase")]
 pub enum AltScreenMode {