I was very unhappy with the "update this dot-path" mechanism I was using earlier; it was hard
for me to read and understand what was happening, and I wrote the darned thing. I decided instead
to go with a hard substitution model; each phase of the wizard is responsible for updating the
*entire* payload, mostly by creating a new payload and substituting the field value associated
with the event.
On the receiver, we have to do that *again* to handle the swapping of providers when the user
chooses one and then another. It looks clunky, and it is, but it's *legible*; a junior dev
could understand what it's doing, and that's the goal.
09fedcacf0