wwstage cgen re-derived fn-ness by NAME: cgident's fn arm gated on
fnretlookup, whose cross-module leaf fallback matches a foreign
same-leaf fn — inside aa.getv the bare `v` (aa's i32 global, stamped
by the #55 prefer fix) took the fn-address arm for main's `fn v` and
emitted LEAQ aa.v(SB) with no deref; the ww_ww-built 794 program
exited 0 instead of 7. cstage reads the checker-stamped type
(cgen.c:4315). Convert the three value-position sites to the stamp
(same predicate-to-stamp conversion as the #14 F7-c7 `&fn` arm):
cgident (now TY_FN -> def -> let, cstage's order — the def-first
order also mis-read a foreign scalar def shadowed by a curmod fn),
the cgdot module-qualified value arm, and the `&ident` #180 arm.
Call-position fnretlookup consumers are unchanged.
The 794 two-file program is now cs==ww byte-identical and both
drivers run exit 7; the carrier retires in the follow-up.