portrait-only: drop landscape rotate prompt + lock to portrait

- Remove RotatePrompt (the "rotate to landscape" overlay) — the app is portrait
  now, so it only blocked the UI.
- page.tsx: best-effort orientation lock switched landscape → portrait.
- Add Playwright-based store-screenshot + icon scripts (scripts/shots.js,
  game.js, icon.js); generated images are gitignored.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/app/page.tsx

@@ -22,7 +22,6 @@ import { ResumeGameBar } from "@/components/online/ResumeGameBar";
 import { CelebrationOverlay } from "@/components/online/CelebrationOverlay";
 import { ErrorBoundary } from "@/components/ErrorBoundary";
 import { PublicProfileModal } from "@/components/online/PublicProfileModal";
-import { RotatePrompt } from "@/components/online/RotatePrompt";
 import { CapacitorBack } from "@/components/CapacitorBack";
 import { useSessionStore } from "@/lib/session-store";
 import { useGameStore } from "@/lib/game-store";
@@ -192,12 +191,11 @@ export default function Page() {
     };
   }, [init]);
 
-  // Landscape-first app (UNO-style): best-effort lock the whole app to landscape
-  // on Android / installed PWA. iOS & desktop reject it harmlessly; the
-  // RotatePrompt covers the portrait case there.
+  // Portrait-first app: best-effort lock the whole app to portrait on Android /
+  // installed PWA. iOS & desktop reject it harmlessly.
   useEffect(() => {
     const o = (screen as unknown as { orientation?: { lock?: (m: string) => Promise<void> } }).orientation;
-    o?.lock?.("landscape").catch(() => {});
+    o?.lock?.("portrait").catch(() => {});
   }, []);
 
   return (
@@ -211,7 +209,6 @@ export default function Page() {
         <ResumeGameBar />
         <CelebrationOverlay />
         <PublicProfileModal />
-        <RotatePrompt />
       </ErrorBoundary>
       <CapacitorBack />
       {loading && null}