Review round 1 (Codex gpt-5.6-terra, MEDIUM): the walk stopped at
December 31st, so the boundary block's next-January days went
unchecked and a year-resetting implementation would pass. The walk
now runs through January 14th of the following year, asserting block
uniformity across the December 31st -> January 1st transition
(including the post-53-week jump), and the walked-year day count is
verified independently of the walk. Suite: 1005 passed.