[DesvoSoft]

Summary

• New setting discord_language (auto default = app language, en, es), exposed through SettingsApi (send_test_notification(..., language=)).
• Default embed titles, descriptions, the test message, durations and plurals are rendered with an explicit catalog (i18n.catalog, resolve_language, format_number(language=)), independent of the UI's current language and thread-safe for the webhook worker.
• Custom templates are never translated (placeholder values stay English); placeholders keep working.
• Settings → Notifications: "Message language" (Same as the app / English / Español), stored by key, labels separate.
• Spanish catalog (formal "usted") compiled and committed.

Quality evidence

• py tools/qa_gate.py: 8/8 READY (1717 tests passed, diff coverage 96%+).
• New tests/test_discord_language.py: en/es defaults, auto follows app language, override wins, templates untouched, durations, plurals, test message; dialog tests for label/key saving.
• Fresh-context adversarial review: no real findings; one low-priority hardening (retry=None) fixed with a regression test.