Preview Flight Booking Session Fare Hold

What /pay would charge right now, given the trip's fare hold (FAC-940).

Computed by the same resolution the charge path runs (identity match, pax, currency, fare-space min(held, live) + locked items) so a hold diagnosis can cite the charge path's own answer instead of guessing from raw data. Read-only: never consumes, stamps, or emits redemption telemetry.