Resolve `size` -> TY_SIZE at the type-name resolver (C lookup_builtin /
ww tinfofornode's N_TNAME chain), mirroring uintptr, both stages. This
makes `size` writable as a type (`let x: size`, struct field, etc.),
the prerequisite for lib/types SIZE_MAX.
Twins every NAME-keyed uintptr arm in the wwstage so it behaves like
the cstage's kind-keyed Type switches (already TY_SIZE-aware from
fold-1): primtypesize + astalign (8B/8-align), primsize + letscalarprim
(8B scalar slot), isinttypeast + isnumerictname (int/numeric). rule-10
symmetric; dead on the size-free selfhost corpus so 990-997 stay byte-id.
Coexists with the size(T) size-of operator (separate c.top SK_FN seed +
N_CALL fold, NOT a type path) and `.size` field access (N_DOT); neither
touched. No c.top SK_TYPE "size" seed (would collide with the operator
seed at check.ww:96). Regenerates w6c/wwdump combined.ww (checker
embedded). New probe 957_size_type_run exercises type-position `size`
and the operator in one scope.