rodboev test-only #4274 (test_issue609, test_sprint3, + 2 others). Linux
assertions stay at full strictness. 63 tests pass. No version stamp (tests-only).
Note: #4273 was NOT included — it touches api/workspace.py runtime (home-expansion
in the blocked-roots boundary), needs a separate full gate.
Co-authored-by: nesquena-hermes <agent@nesquena-hermes>
Co-authored-by: rodboev <rodboev@users.noreply.github.com>