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/lib/router.svelte.ts

@@ -0,0 +1,60 @@
+// Minimal dependency-free hash router. Hash routing survives a reload and works on
+// a file:// origin (Capacitor native packaging), where there is no server to honour
+// deep paths. The route is a reactive rune so screens re-render on navigation.
+
+export type RouteName =
+  | 'login'
+  | 'lobby'
+  | 'new'
+  | 'game'
+  | 'profile'
+  | 'settings'
+  | 'about'
+  | 'notfound';
+
+export interface Route {
+  name: RouteName;
+  params: Record<string, string>;
+}
+
+function parse(hash: string): Route {
+  const path = (hash.replace(/^#/, '') || '/').split('?')[0];
+  const seg = path.split('/').filter(Boolean);
+  if (seg.length === 0) return { name: 'lobby', params: {} };
+  switch (seg[0]) {
+    case 'login':
+      return { name: 'login', params: {} };
+    case 'new':
+      return { name: 'new', params: {} };
+    case 'game':
+      return seg[1] ? { name: 'game', params: { id: seg[1] } } : { name: 'notfound', params: {} };
+    case 'profile':
+      return { name: 'profile', params: {} };
+    case 'settings':
+      return { name: 'settings', params: {} };
+    case 'about':
+      return { name: 'about', params: {} };
+    default:
+      return { name: 'notfound', params: {} };
+  }
+}
+
+export const router = $state<{ route: Route }>({
+  route: parse(typeof location !== 'undefined' ? location.hash : ''),
+});
+
+if (typeof window !== 'undefined') {
+  window.addEventListener('hashchange', () => {
+    router.route = parse(location.hash);
+  });
+}
+
+/** navigate switches the hash route (and forces a re-parse if it is unchanged). */
+export function navigate(path: string): void {
+  const target = '#' + path;
+  if (location.hash === target) {
+    router.route = parse(target);
+  } else {
+    location.hash = path;
+  }
+}