This is meant to capture the substantial followup work based on #369, #374, and #386.

Now that we have generated clients for internal communication, each app should own the structs that define its request bodies (params) and responses (views). The difficulty is that there are a lot of changes to be made before we reach the desired end state, way more than would be reasonable to put in a single PR. Refactors should be done as quickly as possible, but there's going to be a short time where we're in an intermediate state. Also doing a bunch of refactors while we're all hurrying for Milestone 3 is not a good idea. So we're going to have to finish this afterward.

• Simple public views only used in Nexus
  • Project and Organization (done in Structure for moving views and params structs out of common #374)
  • Vpc and friends
• Sled agent things
  • DiskEnsureBody, DiskStateRequested, ShareRequest, ShareResponse (done in Sled agent views/params shuffling #386)
  • InstanceHardware, InstanceEnsureBody, InstanceRuntimeStateRequested
• Runtime state things
  • DiskRuntimeState — kind of interesting because both nexus and sled agent have endpoints that use this struct. this means they should probably each own their own and define a conversion to the other's. There's also the fun fact that Nexus stores this in the db. lots of lines in the diff because it's used in like 60 places
  • InstanceRuntimeState — same deal

This is not a complete list, I'll add more as I go through them.