Ilia Denisov
2d36b54b8d
Closes the documentation gaps from the freshly-audited diplomail implementation. FUNCTIONAL.md gains a §11 "Diplomatic mail" with the full user-facing story across all five stages, mirrored into FUNCTIONAL_ru.md as the project conventions require. A new backend/docs/diplomail-translator-setup.md captures the LibreTranslate operational recipe (Docker image, env wiring, manual smoke test, troubleshooting). The package README gains a "Multi-instance posture" note documenting the deliberate absence of FOR UPDATE in the worker pickup query — single-instance is safe today; multi-instance scaling will revisit the claim mechanism. Two small edge-case tests round things out: malformed LibreTranslate response bodies (single string, short array, empty array, missing field) must surface as errors so the worker falls back instead of crashing; and an empty translation queue must produce zero events on three consecutive Worker.Tick calls. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>