Refactor so include.sh mostly just sets environment variables. Move read_arch_dir to function and call it explicitly (no more need for $NO_ARCH). Make blank_tempdir a function, called explicitly by stages when needed, with some sanity checks. Insert prerequisite tests to later stages so they can detect failure early and provide an explicit erro rmessage, and have those tests happen before blanking $WORK dir, to preserve debugging info. Make buildall.sh depend on prerequisite tests rather than trying to avoid calling later stages (and thus do flow control from asynchronous context). Add FAIL_QUIET option so buildall.sh doesn't spam the log with the new prerequisite error messages.