The e2e-cache.yml workflow repeated the same inline shell block many times
to assert a cache directory exists (and list it), plus inverse checks that a
directory does NOT exist (the gradle2/maven2/sbt2 cache-miss jobs).
Add `__tests__/check-dir.sh` (POSIX sh, executable) with a
`check-dir.sh <dir> [present|absent]` interface and replace every inline
check with a call to it, passing already-expanded $HOME paths to avoid
tilde-expansion pitfalls. The sbt jobs override working-directory, so they
call the helper via $GITHUB_WORKSPACE. Per-OS Coursier conditionals and all
build steps are left unchanged.
Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>
