- endpoint-level: a deployment/program edit via /config/* leaves castle.yaml
globals byte-identical (the exact regression that shipped — the endpoints were
tested but nobody asserted globals survived)
- write_program_file leaves globals untouched (core)
- /secrets/info reports the backend
Still uncovered (tracked): castle mesh CLI, direct-read refactor (dns/stacks),
backend-aware doctor, and all frontend (no test runner configured).