Add detectLocale() that extracts the full locale tag (e.g. "de-DE")
from the request, not just the language. The journal root loader passes
it via LocaleContext so ClientDate renders with the correct locale on
both server and client — no more hardcoded "en-US" fallback.
Also fixes settings page hydration mismatch by using ClientDate for
passkey creation dates instead of inline toLocaleDateString().
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
- /settings with profile, security, and account sections
- Profile: edit display name and bio
- Security: list passkeys with device labels, add/delete with
last-passkey warning
- Account: email change with magic link verification, account
deletion with username confirmation
- Settings link in nav for authenticated users
- E2E tests: auth guard, profile editing, passkey add/delete,
last-passkey warning, account deletion, nav visibility
- i18n: full en + de translations for all settings UI
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>