ui/phase-26: history mode (turn navigator + read-only banner)

Split GameStateStore into currentTurn (server's latest) and viewedTurn
(displayed snapshot) so history excursions don't corrupt the resume
bookmark or the live-turn bound. Add viewTurn / returnToCurrent /
historyMode rune, plus a game-history cache namespace that stores
past-turn reports for fast re-entry. OrderDraftStore.bindClient takes
a getHistoryMode getter and short-circuits add / remove / move while
the user is viewing a past turn; RenderedReportSource skips the order
overlay in the same case. Header replaces the static "turn N" with a
clickable triplet (TurnNavigator), the layout mounts HistoryBanner
under the header, and visibility-refresh is a no-op while history is
active.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

ui/frontend/src/lib/i18n/locales/ru.ts

@@ -90,7 +90,6 @@ const ru: Record<keyof typeof en, string> = {
 	"lobby.error.unknown": "{message}",
 
 	"game.shell.unknown": "?",
-	"game.shell.headline": "{race} @ {game}, ход {turn}",
 	"game.shell.connection.online": "онлайн",
 	"game.shell.connection.reconnecting": "переподключение…",
 	"game.shell.connection.offline": "офлайн",
@@ -105,6 +104,15 @@ const ru: Record<keyof typeof en, string> = {
 	"game.shell.menu.language": "язык",
 	"game.shell.menu.logout": "выйти",
 	"game.shell.coming_soon": "скоро будет",
+	"game.shell.turn.label": "ход {turn}",
+	"game.shell.turn.list_item": "ход #{turn}",
+	"game.shell.turn.prev": "предыдущий ход",
+	"game.shell.turn.next": "следующий ход",
+	"game.shell.turn.open_navigator": "открыть список ходов",
+	"game.shell.turn.close_navigator": "закрыть список ходов",
+	"game.shell.history.viewing": "Просмотр хода {turn} · только чтение",
+	"game.shell.history.return_to_current": "Вернуться к текущему ходу",
+	"game.shell.history.current_badge": "текущий",
 	"game.view.map": "карта",
 	"game.view.table": "таблица",
 	"game.view.table.planets": "планеты",