Stage 17 round 6 (#11/#12): quick-game variant plaques with rules, flag, and move-limit

Each auto-match variant is now a lobby-style plaque: the display name with a flag on the
right (🇺🇸 / 🇷🇺; Erudit uses a bundled minimalist USSR flag SVG) and a one-line rules
summary below — bag size, the ё rule, and bonus differences, sourced from the engine
rulesets (Scrabble 100 · Скрэббл 104, ё a letter · Эрудит 131, ё=е, no centre ×2, +15).
The move-time limit (24h auto-match clock) is shown under the buttons. e2e locks it.

(Multiple-words-per-move is the same for every variant, so it is described in About/landing
rather than repeated on each button.)

ui/src/lib/i18n/en.ts

@@ -45,6 +45,10 @@ export const en = {
   'new.erudit': 'Erudite',
   'new.find': 'Find a game',
   'new.searching': 'Looking for an opponent…',
+  'new.rulesEnglish': '100 tiles · bingo +50',
+  'new.rulesRussian': '104 tiles · ё is a letter · bingo +50',
+  'new.rulesErudit': '131 tiles · ё = е · no centre ×2 · bonus +15',
+  'new.moveLimit': 'Move time: {n} h 00 min',
 
   'game.bag': '{n} in the bag',
   'game.bagEmpty': 'Bag is empty',