An audit found the client already i18n-first: one hard-coded UI string
(the battle-scene aria-label, now keyed) and en/ru already share an
identical 692-key set.
- Persist the locale: i18n.setLocale writes localStorage (galaxy-locale)
and the store boots from stored > browser detection > default, so a
language switch survives reloads.
- tests/i18n-completeness.test.ts: en/ru key-set parity, non-empty
values, and locale persistence.
- Docs: ui/docs/i18n.md; mark F3 done in ui/PLAN-finalize.md.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Adds a minimal Svelte 5 i18n primitive (`src/lib/i18n/`) backing the
login form, the layout blocker page, and the lobby placeholder.
SUPPORTED_LOCALES drives both the picker and the runtime lookup;
adding a language is a two-step change inside `src/lib/i18n/`.
Login form gains a globe-icon language dropdown (English / Русский
in their native names), defaulting to navigator.languages with `en`
as the fallback. Switching the locale re-renders the form in place;
on submit, the locale rides in the JSON body of `send-email-code`
because Safari/WebKit silently drops JS-set Accept-Language. Gateway
gains a body `locale` field that takes priority over the request
header for preferred-language resolution.
Email and code inputs disable browser autofill / suggestions
(`autocomplete=off` + `autocorrect=off` + `autocapitalize=off` +
`spellcheck=false`) so Keychain / address-book pickers and
remembered-value dropdowns no longer fire on focus.
Cross-cuts:
- backend & gateway openapi: clarify that body `locale` is honored.
- docs/FUNCTIONAL{,_ru}.md §1.2: document body-vs-header priority.
- gateway tests: body `locale` overrides Accept-Language; blank
body `locale` falls back to header.
- new ui/docs/i18n.md; cross-links from auth-flow.md and ui/README.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Ilia Denisov