This gist is a TDD-style hand-off between the test author (this session)
and the implementation agent (working on the store server repo).
The implementation agent's job is to make every xfail test in
test_round12_next_features.py flip to XPASS, and then strip the xfail
markers, so the file becomes 23/23 green permanent regression guards.
The test author will keep this gist and the test file in sync until the