iface_slot reads the declaration slot assign_slots recorded, so a call site
emits an offset the class table actually has and refuses a method the interface
does not declare. The x128 fixture proves one call site reaching two classes,
one object reaching two interface tables, a nested call with a one-byte result,
and byte/word arguments returning a word with the frame stack restored, while
self stays the underlying object.

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

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.

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

Classes now build one table per implemented interface, in implements order with
one two-byte entry per interface slot, and a failed class rolls back so a
missing method address is refused instead of dispatching to zero. The MAP gains
one TABLE record per table, and the x128 fixture checks table contents, distinct
per-class tables, both rollback paths, and the exact MAP text.

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