Hojun-Cho
a5ca21ddba
Phase 2 step 2. The N_INDEX element-stride for str hardcoded esz=1;
route it through the type table (cstage ty_u8->size, wwstage
primtypesize("u8")) so str's element width tracks the u8 SSoT. When
the TY_STR collapse (Phase 2 step 5) folds str onto the slice-of-u8
path, these sites need no second edit. Byte-id-neutral: u8 size is 1,
so emitted stride is unchanged; full test (incl 990-997 byte-id
gates) green.