Nothing promoted yet, and that is a real number rather than a placeholder for one.

This file exists because git does not track an empty directory, and the directory has to exist
before `make check` can settle what is in it -- which is the point of wiring the target before the
first promotion: the day somebody promotes a case, it is measured on the same commit, and the row
in design/gates.md moves from `partial` to `held` because something finally has a subject.

See ../README.md. `load_cases` reads `*.json` only, so this file is inert.
