Hojun-Cho
901ddf20b9
cgwidentaggedstore/storebp/cgwidentagremap took a type *node and re-derived the tagged shape via resolvetagged + N_TTAGGED.list walks. Migrate them onto the stamped tinfo (the store-side parallel of #66's match-side flip): dst is now the tagged *tinfo (peel TY_NAMED->du, gate TY_TAGGED), variant lookup + tag-remap read tinfo.params by typeeq, mirroring cstage cg_widen_tagged_store / cg_widen_tag_remap / cg_tag_for_variant (cmd/w6c/cgen.c:1273/1177/503). The N_CAST widening test flips from surface-name streq to `castu==dt || (castu tagged && typeeq(castt,dst))` (cgen.c:1295). Node-form flatvariantidx/taggedvariantindex become thin shims over new tinfo cores (flatvariantidxt/taggedvariantindext) so node-side callers (cgreturn cgenstmt:269, pushargs cgenutil:192) are untouched. The 9 cgwidentaggedstore callers pass node.type_ (each already istaggedtype/slotsize-gated). resolvetagged is retained for its 7 match-side callers. Incidentally retires two latent ww-vs-cstage divergences, both byte-id-neutral on the corpus: the old N_CAST test set castisdst for ANY N_TTAGGED regardless of type equality (cstage guards on type_eq), and the old remap walked the UNflattened src.list (cstage walks the flattened params). Unblocks cgassign's indexvaluetnode drop (#69/#61d). make test 134/134, byte-id 990-997 hold.