Tax breakdown is displayed in order confirmation

Displaying tax as a line item only on the checkout page — and omitting it from the cart summary, order confirmation page, and confirmation email — violates both FTC Mail, Internet, or Telephone Order Merchandise rules and EU Consumer Rights Directive 2011/83/EU Article 6, which require clear pre-payment disclosure of total costs. When the tax amount is absent from the confirmation email, customers have no documentation of what they were charged for taxes, which becomes a dispute point during returns or accounting reconciliation. A static Tax: $0.00 placeholder is worse than omission — it actively misleads the customer about their actual tax liability.

Add a dynamically computed tax line to the order confirmation component in components/OrderConfirmation.tsx:

// components/OrderConfirmation.tsx
export function OrderConfirmation({ order }: { order: Order }) {
  return (
    <div className="order-summary">
      <div className="flex justify-between">
        <span>Subtotal</span>
        <span>${(order.subtotal / 100).toFixed(2)}</span>
      </div>
      <div className="flex justify-between">
        <span>Shipping</span>
        <span>${(order.shipping / 100).toFixed(2)}</span>
      </div>
      <div className="flex justify-between">
        <span>Tax{order.tax_jurisdiction ? ` (${order.tax_jurisdiction})` : ''}</span>
        <span>${(order.tax / 100).toFixed(2)}</span>
      </div>
      <div className="border-t pt-2 flex justify-between font-bold">
        <span>Total</span>
        <span>${(order.total / 100).toFixed(2)}</span>
      </div>
    </div>
  )
}

Mirror the same four line items (subtotal, shipping, tax, total) in the order confirmation email template. Never render a static $0.00 for tax — pull the value from the stored order record.