Add capability to pass data field in server response to sources

[alexj]

We have had a few requests for us to pass data from the recipient all the way back to the source. For example, one customer returns a redirect URL that the vendor needs to be able to act on. Another sends a unique reference ID back to the source.

Alex, assigning to you as you mentioned we had this feature previously that we might be able to build off of.

We'll also need to work through the front-end experience in the flow for this.

[alexkwolfe]

FWIW, any integration can already do this. It's really more a question of adding a way to tell the integrations that they should do this, and which values to pass back. We obviously don't want to pass everything back, otherwise the source gets a look at a bunch of information they probably shouldn't, such as which upstream buyers and systems were contacted.

This configuration is something that needs to be determined by the user. So I think this is almost entirely a front-end experience issue.