wwstage computed tagged sizes/tags off the raw variant list — size()
folded wrong constants (size((*u8|void)) 16 vs 8, (i32|never) 16 vs 4)
and duplicate variants got divergent tag numbering vs cstage, while
ww's own cgen layout folded nullable but its size() didn't. Make
tinfofornode's N_TTAGGED arm the normalization SSoT mirroring cstage
resolve_type (check.c:801-882): never-drop, duplicate dedup via
structural typeeq, single-variant collapse, nullable fold on the
normalized pair; astsize/astalign delegate, and voidvariantindex reads
the normalized ti.params (cgen.c:900-911) so construct/match/void tag
readers agree. Corpus-neutral (zero-move on all combineds);
989_tagnorm_run pins the folds dual-stage, red-proven. Review items
#1/#3; residual #45 filed (AST-keyed nullable gate at global emit).