Price Modification

Review queue for agent-requested changes to a cart's final total.

📄️ List price-modification requests to review (paginated)

Returns the requests the caller may act on — those on carts in a channel they approve for (`cart_approver`) — plus any they raised themselves. Booking-side fields and filters (`bookingStatus`, `paymentMode`) are only populated once the cart has checked out, so they are empty for a request still `PENDING`.

📄️ Listings for the queue's listing filter

Only listings that appear on a request the caller can see, so a chosen option always narrows to something. Feed `id` back as `listingId`.

📄️ One price-modification request, with the full priced cart behind it

Powers the review sheet: the request, the requesting agent's contact details, a presigned URL for the supporting document, and the cart itself — whose `summary` drives the price breakdown and whose `items[].meals` / `items[].vas` drive the Meals and Value Added Services panels. 404 when the cart is not visible to the caller; 403 when it is visible but they do not approve for its channel.