Extend the shared type model so SPIR-V's OpTypeBool and OpTypeArray (whose length
is a constant <id>, not a literal) lower cleanly:
- ir.Type_Kind gains BOOL (a distinct boolean; LLVM i1 will use it too).
- ir.Type gains len_ref: Id -- an ARRAY length carried as a constant <id>
(alongside the existing literal count for dialects with literal lengths).
- type_bool / type_array constructors.
SPIR-V codec: OpTypeBool <-> Type{.BOOL}; OpTypeArray <-> Type{.ARRAY, elem,
len_ref}. Test bool_and_array round-trips byte-exact -> 6 passed.
NOTE: a spec-valid module orders an array's length constant before the array
type; the codec round-trips the shape byte-exact regardless, but emitting the
types/constants section in dependency order is a follow-up.
fe27dcdbd4