[TUI] Split multiline commands (#2202)

Fixes:
<img width="5084" height="1160" alt="CleanShot 2025-08-11 at 16 02 55"
src="https://github.com/user-attachments/assets/ccdbf39d-dc8b-4214-ab65-39ac89841d1c"
/>

codex-rs/tui/src/history_cell.rs

@@ -401,7 +401,7 @@ impl HistoryCell {
         let mut lines: Vec<Line> = vec![Line::from("⚙︎ Working")];
 
         for (i, parsed) in parsed_commands.iter().enumerate() {
-            let str = match parsed {
+            let text = match parsed {
                 ParsedCommand::Read { name, .. } => format!("📖 {name}"),
                 ParsedCommand::ListFiles { cmd, path } => match path {
                     Some(p) => format!("📂 {p}"),
@@ -419,11 +419,14 @@ impl HistoryCell {
                 ParsedCommand::Unknown { cmd } => format!("⌨️ {}", shlex_join_safe(cmd)),
             };
 
-            let prefix = if i == 0 { "  L " } else { "    " };
-            lines.push(Line::from(vec![
-                Span::styled(prefix, Style::default().add_modifier(Modifier::DIM)),
-                Span::styled(str, Style::default().fg(light_blue())),
-            ]));
+            let first_prefix = if i == 0 { "  L " } else { "    " };
+            for (j, line_text) in text.lines().enumerate() {
+                let prefix = if j == 0 { first_prefix } else { "    " };
+                lines.push(Line::from(vec![
+                    Span::styled(prefix, Style::default().add_modifier(Modifier::DIM)),
+                    Span::styled(line_text.to_string(), Style::default().fg(LIGHT_BLUE)),
+                ]));
+            }
         }
 
         lines.extend(output_lines(output, true, false));
@@ -1102,3 +1105,26 @@ fn format_mcp_invocation<'a>(invocation: McpInvocation) -> Line<'a> {
     ];
     Line::from(invocation_spans)
 }
+
+fn shlex_join_safe(command: &[String]) -> String {
+    match shlex::try_join(command.iter().map(|s| s.as_str())) {
+        Ok(cmd) => cmd,
+        Err(_) => command.join(" "),
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn parsed_command_with_newlines_starts_each_line_at_origin() {
+        let parsed = vec![ParsedCommand::Unknown {
+            cmd: vec!["printf".into(), "foo\nbar".into()],
+        }];
+        let lines = HistoryCell::exec_command_lines(&[], &parsed, None);
+        assert!(lines.len() >= 3);
+        assert_eq!(lines[1].spans[0].content, "  L ");
+        assert_eq!(lines[2].spans[0].content, "    ");
+    }
+}