Stage 7 (wip): UI shell, libs, mock transport, screens (lobby->game), e2e smoke

- plain Svelte 5 + TS + Vite (no SvelteKit); CSS-token design system (Telegram-ready), hash router, IndexedDB session
- pure libs: domain model, premium/value maps ported from solver, board replay, placement state machine, i18n en/ru
- in-memory mock transport + seed data; pnpm start runs lobby->active game->board with no backend
- board: pointer-drag + tap placement, MakeMove (popup / 1s-hold commit), two-state zoom, blank chooser, exchange, hint, word-check, chat
- Playwright smoke (mock) green; svelte-check clean; mock bundle ~37 KB gzip

ui/src/screens/About.svelte

@@ -0,0 +1,22 @@
+<script lang="ts">
+  import Header from '../components/Header.svelte';
+  import { t } from '../lib/i18n/index.svelte';
+
+  const version = '0.7.0';
+</script>
+
+<Header title={t('about.title')} back="/" />
+<main class="page">
+  <h2>{t('app.title')}</h2>
+  <p>{t('about.description')}</p>
+  <p class="muted">{t('about.version', { v: version })}</p>
+</main>
+
+<style>
+  .page {
+    padding: var(--pad);
+  }
+  .muted {
+    color: var(--text-muted);
+  }
+</style>