This is useful for LSPs who wish to create a just-in-time channel for end users
receiving a lightning payment. These fake scids will be encoded into route
hints in end user invoices, and signal to LDK to create an event triggering the
JIT channel, after which the payment will be received.
Co-authored-by: John Cantrell <johncantrell97@gmail.com> Co-authored-by: Valentine Wallace <vwallace@protonmail.com>