Rationale
Every generated instruction file exists, matches the stamp it carries, and is never silently overwritten after a hand edit.
Required behaviour
Every generated instruction file exists, matches the content it declares, and is never silently overwritten after a hand edit.
Failure behaviour
A violation is a FAIL finding under the category projection, and the command that found it exits 10. Under watch the same violation is reported as drift and the command exits 11.
Verification
mj_validate_projection decides it, dispatched from doctor, watch. The behavioural case test/cases/03_update.sh proves it, and CI runs that case.