SANITY-FAIL report showed megacaps/ETFs already at empirical 2016-01-04 floor
(2649 bars) after deepen; check wrongly required ~2013. Pass when megacaps leave
the old 2021 two-tier floor and match SPY; XLC listing exception retained.
Terminal follow-up for Task 1: detect/refetch shallow two-tier symbols and sector
ETFs at 5000d, regenerate manifest, run ONE liquid-1500 harness with era split, grade
mom_12_1_sector_resid mechanically. Bundled as run_tier1_macbook.sh --sector-resid-deep.
dennisthiessen