distro-build/drive-clients: add `--clean' argument
raco setup: fix dependency checking for more nested directories

I'm not sure why a problem with the "package closure" operation
didn't create problems earlier for `raco setup' --- or maybe it
did, but they're difficult to see.

Also, reduce redundancy in reporting of reasons for dependency
mismatches (but keep multiple reports of the same missing
dependency but for different reasons).
more auto package-dependency repairs

As detected by the repaired `raco setup'.