fix(tui/scroll): translate wheel events in alt screen

Closes just-every/code#168.

codex-rs/tui/src/tui.rs

@@ -2,6 +2,7 @@ use std::io::Result;
 use std::io::Stdout;
 use std::io::stdout;
 use std::io::BufWriter;
+use std::io::Write;
 
 use codex_core::config::Config;
 use crossterm::cursor::MoveTo;
@@ -76,6 +77,7 @@ pub fn init(config: &Config) -> Result<(Tui, TerminalInfo)> {
     crate::syntax_highlight::init_highlight_from_config(&config.tui.highlight);
 
     execute!(stdout(), EnableBracketedPaste)?;
+    enable_alternate_scroll_mode()?;
     // Enable focus change events so we can detect when the terminal window/tab
     // regains focus and proactively repaint the UI (helps terminals that clear
     // their alt‑screen buffer while unfocused). However, certain environments
@@ -250,6 +252,7 @@ pub fn restore() -> Result<()> {
     execute!(stdout(), DisableBracketedPaste)?;
     // Best‑effort: disable focus change notifications if supported.
     let _ = execute!(stdout(), DisableFocusChange);
+    disable_alternate_scroll_mode()?;
     execute!(stdout(), DisableMouseCapture)?;
     disable_raw_mode()?;
     // Leave alternate screen mode
@@ -266,6 +269,7 @@ pub fn restore() -> Result<()> {
 pub fn leave_alt_screen_only() -> Result<()> {
     // Best effort: disable mouse capture so selection/scroll works naturally.
     let _ = execute!(stdout(), DisableMouseCapture);
+    disable_alternate_scroll_mode()?;
     // Also disable bracketed paste and focus tracking to avoid escape sequences
     // being echoed into the normal buffer by some terminals.
     let _ = execute!(stdout(), DisableBracketedPaste);
@@ -299,6 +303,7 @@ pub fn enter_alt_screen_only(theme_fg: ratatui::style::Color, theme_bg: ratatui:
         let _ = execute!(stdout(), EnableFocusChange);
     }
     let _ = execute!(stdout(), EnableBracketedPaste);
+    enable_alternate_scroll_mode()?;
     execute!(
         stdout(),
         crossterm::terminal::EnterAlternateScreen,
@@ -311,6 +316,20 @@ pub fn enter_alt_screen_only(theme_fg: ratatui::style::Color, theme_bg: ratatui:
     Ok(())
 }
 
+fn enable_alternate_scroll_mode() -> Result<()> {
+    let mut handle = stdout();
+    handle.write_all(b"\x1b[?1007h")?;
+    handle.flush()?;
+    Ok(())
+}
+
+fn disable_alternate_scroll_mode() -> Result<()> {
+    let mut handle = stdout();
+    handle.write_all(b"\x1b[?1007l")?;
+    handle.flush()?;
+    Ok(())
+}
+
 /// Clear the current screen (normal buffer) with the theme background and reset cursor.
 // Removed: clear_screen_with_theme — we no longer hard-clear the normal buffer in terminal mode.