v1.58.17

[1.58.17] — 2026-05-20

fix(i18n): I-2 — saved-research dates now use Intl.RelativeTimeFormat per locale. The formatRelative() helper in public/js/views/deep.js returned hardcoded English today / 1d ago / Nd ago regardless of UI language. Replaced with Intl.RelativeTimeFormat(I18n.getLang(), { numeric: 'auto' }) — the browser-native localized "today/yesterday/N days ago" string (сегодня/вчера, 今日/昨日, etc.). Dates older than 7 days fall back to Intl.DateTimeFormat(locale, { dateStyle: 'medium' }). Defensive try/catch keeps the old English fallback for ancient browsers without Intl. 912 → 913 unit. (I-2)

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