Thrift integration needs better support

[Matt-Esch]

Currently we have two processes that independently handle thrift, and it isn't clear to me how to interact with the thrift spec and the related generated structs. We probably need to look at generating thrift structs as part of the build step, and also proving the compiled specs in an accessible way, otherwise modules that require access to thrift specs are going to be reading from disk and manually compiling the specs on the fly.