single source of truth for the rnbo directory?

[jinpavg]

at present, every RNBO export gets a folder with its own rnbo dir -- to simplify dependencies (what if some version of RNBOMetasound depends on a version of RNBO but some of the exported patches are older?) could we somehow have just one rnbo dir which is the one we know will be used?

[x37v]

In the short term, we could also consider iterating over all of the exports and detecting which version of rnbo they were exported with and at least throwing up a warning if they don't all match