Reverts the re-regression introduced in 410b91e2. Gitea Actions
(act_runner) does not implement the v4 artifact protocol — jobs report
failure even when all tests pass. Pins all three call sites back to @v3
and adds load-bearing inline comments pointing to ADR-014 / #557.
This commit makes the grep guard added in the previous commit GREEN.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Verification mechanism for the 20-run acceptance criterion of issue #553.
Triggered manually via workflow_dispatch, runs the full coverage suite 20×
in parallel against a single SHA, asserts zero `[birpc] rpc is closed`
lines in every cell.
One fire, parallel cost (~one main-job's wall-clock), deterministic signal
for the teardown race. Cheaper than 20 sequential push events and tests
the same property the AC names.
Closes the verification gap raised by Tobias and Elicit in the issue
discussion.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
