The set of uploads subdirectories is hand-mirrored between the image build
and the boot-time mkdir in server/src/index.ts, and drift is invisible
until a user whose bind-mounted uploads dir is not writable by node hits an
EACCES on the first upload to the missing dir (#1762).
Parse both lists and assert they match, with a guard case so the regexes
cannot silently match nothing and pass vacuously.
jubnl