Discovers test/wcc/data, hard-pins corpus identity (1,224 fixtures,
314 error / 12 compile / 136 run / 762 run-exit, sha256 name hash),
schedules both frontend cells per fixture through os.exec with
per-cell capture dirs, and emits the strict wwfix TSV result stream.
integration.sh is the black-box owner of the CLI/protocol boundary.
Single-directory package-test planner: discovers *.ww, groups white-box
and external <pkg>_test sources, composes the combined test package,
builds it through the sibling ww driver, and runs it with the runtime's
-package/-list/-timeout-ms contract. test/package holds its E2E corpus
and the manual runtime fixture set.
