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.
for-range destructure of an element with a slice- or tuple-typed field
strode by the default 8 (paramfieldsize had no N_TSLICE/N_TTUPLE arms),
silently reading the wrong words (review finding #43; live repro
cs=42 vs ww=8). Add the arms routed through tinfo per rule 13.
989_tupfieldsize_run pins cs==ww (red 1/2 pre-fix); rows assert
convergence, not absolutes — cstage's own single-word destructure-load
bug is filed as task #40. The N_TARRAY arm is deferred (task #39,
rule-7 comment at the fall-through).
