Mobile inbox i18n hotfix
- Adds the mobile inbox detail/contact labels to the namespaces the mobile conversation pane actually renders from, across every app locale.
- Fixes the Italian production
MISSING_MESSAGE: inbox.mobile.detail.* (it)console errors and the associated React hydration fallout on/inbox. - Adds regression coverage so every configured app locale must carry the mobile detail/contact keys consumed by the mobile inbox layout.