The runs-list query's `ref` filter matches only a fully-qualified ref,
while the listing prints `prettyref` (`main`, `#3967`). So no value a
caller can read off the output was accepted by the filter, and the
rejection rendered as "no matching runs" — indistinguishable from a
branch that has never been built.
Qualify the value before it reaches the query: `refs/...` passes
through, `#N`/`N` becomes the pull head ref, anything else becomes a
branch. A slash cannot mark an already-qualified ref, since branch
names contain them.
Not shared with ci-rerun: its `ref` is a workflow_dispatch body field
taking a bare branch name, so the same normalisation would break it.
Closes#3970
8a48f958b8