Function is_light_terminal

crates/openshell-tui/src/theme.rs:220–226

Detect whether the terminal has a light background using OSC 11. Uses `terminal-colorsaurus` to send an OSC 11 query to the terminal, which returns the actual background RGB color. This works reliably on iTerm2, Terminal.app, `WezTerm`, Alacritty, and most modern terminals. Falls back to `false` (dark) if the terminal doesn't respond to the query (e.g. `TERM=dumb`, piped output, very old termina

()

/// Falls back to `false` (dark) if the terminal doesn't respond to the
/// query (e.g. `TERM=dumb`, piped output, very old terminals).
fn is_light_terminal() -> bool {
    use terminal_colorsaurus::{QueryOptions, ThemeMode as ColorsaurusMode};
    matches!(
        terminal_colorsaurus::theme_mode(QueryOptions::default()),
        Ok(ColorsaurusMode::Light)
    )
}

#[cfg(test)]
mod tests {