Adds `Bit_write_surfaces_device_rejection_status` to AbLegacyBitRmwTests,
verifying that a non-zero libplctag status returned by the parent-word write
in WriteBitInWordAsync propagates as a non-Good OPC UA StatusCode rather than
being silently swallowed. Added a minimal `WriteStatusOverride` hook to
FakeAbLegacyTag (test-project-only) so the read half of the RMW still
returns 0/Good while the write half returns the seeded error code.
Joseph Doherty
c48f299994