Cart Amount Modification

Agent override of the cart's final (post-GST) total — decrease (needs approval) / increase (surcharge).

📄️ Request an override of the cart's final (post-GST) total

The agent enters `targetTotal` (the grand total the customer should pay). A target BELOW the current total is a DECREASE — recorded as a PENDING request for an approver; the cart total is unchanged until approved. A target ABOVE is an INCREASE — applied immediately as a surcharge (no approval). The post-GST delta is converted to a pre-GST adjustment and shown as a `MOD-xxxx` line. Returns the cart (with the increase applied, or the pending request surfaced on `amountModification`).

📄️ Withdraw the cart's pending modification request

Withdraw the cart's pending modification request

📄️ Approve a pending decrease request

Approver-only. The caller must be listed in `cart_approver` for the cart's channel, and the discount must be within their `max_discount_percentage`. On approval the discount line applies and the cart total drops to the requested amount.

📄️ Reject a pending modification request

Approver-only (see approve). The request is marked REJECTED with an optional note; the cart total is unaffected.