Returns a single order (Order) with its full detail: line items (items), the instalment
schedule (installments), the customer, fulfillments, refunds (reversals), voids, and the
complete statusHistory. Requires scope orders:read.

status, paymentType, channel, each instalment's status and each history row's
fromStatus/toStatus are enum names ("Confirmed", "PayByInstalments", "Online",
"Paid"), never integers. Amounts: capturedAmount and collectedAmount are what the customer
has paid so far, fulfilledAmount is what you have shipped, refundedAmount/reversedAmount
what has been refunded, voidedAmount what was cancelled after confirmation, and
refundableAmount is what you can still refund.

{id} is the Qasimha order id (installmentId) returned when the session was created.
Orders belonging to other merchants return 404.