Match intro "players joining" loading screen + i18n fix; checkpoint

- MatchIntroOverlay: UNO-style pre-game reveal — the 4 seats animate into the
  table (with "?" placeholders until each player's data streams in for live
  matches), a 3-2-1-GO countdown, then the table shows. Wired via game-store
  matchIntroPending/consumeIntro, rendered online-only in GameScreen.
- Fix: intro.found / intro.getReady / intro.go existed only in the Persian dict;
  added the English strings (would have shown raw keys to EN users).
- Checkpoint of the in-progress UI/social batch (CoinsPill, shop titles section,
  friend-request rate limit, etc.) — all green.

Verified: tsc + next build + scripts/sim.ts + dotnet build server/Hokm.slnx all pass.

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

src/lib/i18n.tsx

@@ -221,6 +221,9 @@ const fa: Dict = {
   "mm.found": "بازیکنان پیدا شدند!",
   "mm.ready": "آماده شروع",
   "mm.fillHint": "اگر بازیکن آنلاینی پیدا نشود، ربات‌ها جایگزین می‌شوند",
+  "intro.found": "بازیکنان آماده‌اند!",
+  "intro.getReady": "بازی در حال شروع است…",
+  "intro.go": "شروع!",
   "mm.cancel": "لغو",
   "mm.start": "ورود به بازی",
 
@@ -379,6 +382,10 @@ const en: Dict = {
   "match.addFriend": "Add",
   "match.sent": "Sent",
 
+  "intro.found": "Players ready!",
+  "intro.getReady": "The game is starting…",
+  "intro.go": "GO!",
+
   "seat.you": "You",
   "team.us": "Us",
   "team.them": "Them",