it_find selects the table a class emitted for an interface, refusing a pair the
class does not implement, and if_assign, if_arg_push, if_elem_store, and
if_elem_load give assignment, argument passing, field, and array storage one
API that keeps all four value bytes. Two x128 fixtures prove the class and null
conversions, verbatim copies, array stride, argument layout, and the result
area, while the semantic suite still rejects an invalid conversion.

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Co-Authored-By: Codebuff <noreply@codebuff.com>

Freeze the four-byte fat reference, canonical null, slot/table layout,
and the IF_RESULT return area so interface dispatch and table emission can
build on one documented contract.

Generated with Codebuff
Co-Authored-By: Codebuff <noreply@codebuff.com>