Theorem 6.8

Theorem 6.8 (Convergent strong-trace presentation). For fixed finite $d,k,\Gamma$, oriented endpoint detours and literal guarded unrolls form a terminating confluent graph-local presentation of strong equivalence. Two histories have the same strong trace if and only if they reduce to the same SELF-eager history. A length-$n$ history normalizes in at most $dn$ row moves when $U$ counts as one whole-row move.