feat(stats): best-move word, moves & hint-share, and a hint-count fix (#81)

The statistics screen gains real depth, plus a hint-count bug fix found along the way.

- Best move per variant: the screen shows the actual best-move word (drawn as game
  tiles; a wildcard shows its letter but no value), broken down by game variant, empty
  variants omitted. New account_best_move table, written at game finish.
- Moves & hint share: two new lifetime tiles — the player's play count and the share of
  plays that used a hint — from summed account_stats counters (moves, hints_used).
  Honest-AI games are excluded, like the rest of the stats.
- Hint-count fix: the in-game hint badge no longer goes stale across games. The global
  wallet now rides the wire apart from the per-game allowance (wallet_balance on
  StateView/HintResult/StatsView), so the client reads the live wallet rather than a
  per-game snapshot; game_players.hints_used now counts every hint (allowance + wallet),
  its true per-game total.
- Account merge: sums the new moves/hints_used counters and merges the per-variant best
  moves (higher score kept), which it previously dropped.
- Admin: the user card shows Moves and Hints used.
- UI polish: tab/label wording, game-over text, and e2e selectors hardened against label
  changes.

All wire additions are trailing (backward-compatible). Docs (ARCHITECTURE, FUNCTIONAL +ru,
UISN_DESIGN) updated in step.

platform/telegram/internal/render/render.go

@@ -126,9 +126,9 @@ var english = phrases{
 	yourTurnExchange: "%s: swapping tiles, your turn.",
 	yourTurnPass:     "%s: passing, your turn.",
 	yourTurnMoved:    "%s moved, your turn.",
-	gameOverWon:      "Game over — you won! Score %s",
-	gameOverLost:     "Game over — you lost. Score %s",
-	gameOverDraw:     "Game over — a draw. Score %s",
+	gameOverWon:      "Game over - 🏆 you won! Score %s",
+	gameOverLost:     "Game over - you lost. Score %s",
+	gameOverDraw:     "Game over - a draw. Score %s",
 	nudge:            "You were nudged — it's your turn.",
 	nudgeBy:          "%s: Waiting for your move 🤭",
 	matchFound:       "Your game is ready.",
@@ -144,8 +144,8 @@ var russian = phrases{
 	yourTurnExchange: "%s: меняю фишки, ваш ход.",
 	yourTurnPass:     "%s: пропускаю ход, ваш ход.",
 	yourTurnMoved:    "%s сходил(а), ваш ход.",
-	gameOverWon:      "Игра окончена — вы выиграли! Счёт %s",
-	gameOverLost:     "Игра окончена — вы проиграли. Счёт %s",
+	gameOverWon:      "Игра окончена — 🏆 Вы выиграли! Счёт %s",
+	gameOverLost:     "Игра окончена — Вы проиграли. Счёт %s",
 	gameOverDraw:     "Игра окончена — ничья. Счёт %s",
 	nudge:            "Вас поторопили — ваш ход.",
 	nudgeBy:          "%s: Жду Вашего хода 🤭",