Cannot easily migrate project node between teams

A user reported that they were not expecting to have to reconfigure their project nodes when copying a flow between teams.

It's a non-typical use case where this user deploys the same set of flows to different teams for each of their customers. The instances in the team have standard names, and the project nodes are configured to send/receive to instances by their name.

However, we store the instance ID in the node config. This is *not* portable between teams, so the node(s) need to be edited and saved (even if no changes are made because the select box picks the first instance in the list that happens to be the right one).

Not sure how we can best improve on this. If we store the instance name, we'll need to do a lookup to get the ID as that's what we use in the underlying topic structure - if there's any issue doing that lookup, it becomes a potential point of failure for the flows.

I've raised #119 which was related to the lack of feedback on this misconfiguration being deployed.