12.13 the two states UNKNOWN holds and why one of them presses nothing; 12.14 a frontier no walk
can reach, remembered per map rather than windowed; 12.15 what the ratchet's stall window cannot
see; 12.16 what is still in the way of the badge, measured rather than fixed -- the town errands
being session state, GO FRONTIER still being most of the run in Pewter City, and the whole-map
grid being refused on every frame the fly is mid-step (118 of 120 standing still, and the
disagreement is exactly one tile row in the direction of travel).
13.1's pad-empty table gains the row for the one empty pad that ends itself, and the ladder's
recovery budgets carry the amendment to the 2026-09-17 progress rule.