Hojun-Cho
2a2ac49c64
The per-binding copy loop moved ONE word of a 24B str/slice binding — .len and .cap read zero/garbage in BOTH stages (byte-identical, the deepest both-wrong-identical of the drain: the F7-era stride fix asserted convergence without re-measuring the absolute). Copy the full extent for an sz>8 str/slice binding; the rewritten 989_tupfieldsize pins all three header words with sliced caps so cap!=len has teeth. The tagged-binding arm remains open as task #53 (wwstage paramfieldsize). Review-era task #40, recategorized #263 fused. Both stages move in one commit: one emission contract; splitting would leave the byte-id gates red between the halves.