Native review of the German, French, Spanish and Chinese GDPR, retention and masking site strings #1055

Summary

The German, French, Spanish and Chinese site strings about GDPR, retention and masking were written without a native-speaker review. English and Turkish are authoritative; the other four locales are a deferred tier (docs/standards/localization.md), and the owner accepted the exception for these strings in pull requests #1000 and #1050. They state legal facts (what forgelm reverse-pii and forgelm purge are for, what is and is not changed), so a wrong nuance in a translation is a compliance statement that nobody has checked.

Strings to review (key x locale de, fr, es, zh)

• home.cap.gdpr.body, home.use.domain.body, features.data.pii.body
• compliance.gdpr15.body, compliance.gdpr17.body, compliance.art10.body
• features.gov.access.title / .body, features.gov.purge.title / .body
• privacy.body (the "Data-subject rights" paragraph)
• wizard.retention.title, wizard.retention.hint, wizard.retention.audit_log.hint, .staging.hint, .ephemeral.hint, .raw_documents.hint

What a reviewer checks

• The legal terms: data subject (betroffene Person / personne concernée / interesado / 数据主体), access (Auskunft / droit d'accès / acceso), erasure (Löschung / effacement / supresión / 删除), and the citation style for GDPR articles and paragraphs.
• The caveats survive: "an input to an Article 15 response", "one step of an Article 17 erasure", "trained weights are not changed", "matching is literal and case-sensitive", "masking is opt-in (--pii-mask)", "a horizon is only reported, never enforced; 0 stops the report".
• Natural wording, consistent terminology within each locale (for example "journal d'audit" vs "log d'audit" in French).

Acceptance criteria

• One native reviewer per locale (or a documented decision to leave a locale at English fallback) has read every string above and the corrections are applied in site/js/translations.js.
• node --test tests/site/*.test.cjs stays green (the tests pin the caveats per locale).
• The review (reviewer, locale, date) is recorded in the pull request. docs/standards/localization.md has no place for native-review records yet, and its locale-status section is being reworked under [Phase 16] S16 — Documentation source-of-truth and localization governance #902 (localization governance); once [Phase 16] S16 — Documentation source-of-truth and localization governance #902 has landed, record the review there too.

Context

Related: #948 (native review of monitoring-plan and webhook copy). Labels i18n and help wanted apply: this needs people who read the languages, not a code change.