Function gateway_use

crates/openshell-cli/src/run.rs:586–602

Set the active gateway.

(name: &str)

/// Set the active gateway.
pub fn gateway_use(name: &str) -> Result<()> {
    // Verify the gateway exists
    get_gateway_metadata(name).ok_or_else(|| {
        miette::miette!(
            "No gateway metadata found for '{name}'.\n\
              Register it first with: openshell gateway add <endpoint> --name {name}\n\
              Or list available gateways: openshell gateway select"
        )
    })?;

    save_active_gateway(name)?;
    eprintln!("{} Active gateway set to '{name}'", "✓".green().bold());
    if let Some(warning) = gateway_env_override_warning(name) {
        eprintln!("{} {warning}", "⚠".yellow().bold());
    }
    Ok(())
}

fn gateway_env_override_warning(selected_name: &str) -> Option<String> {
    let env_name = std::env::var("OPENSHELL_GATEWAY").ok()?;