ui/phase-12: order composer skeleton

OrderDraftStore persists per-game command drafts in Cache; the
sidebar Order tab renders the list with a per-row delete control.
The layout passes a `historyMode` prop through Sidebar / BottomTabs
as a constant `false`, so Phase 26 only flips the source.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

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

@@ -118,7 +118,8 @@ const en = {
 	"game.sidebar.tab.order": "order",
 	"game.sidebar.empty.calculator": "coming soon",
 	"game.sidebar.empty.inspector": "select an object on the map",
-	"game.sidebar.empty.order": "coming soon",
+	"game.sidebar.empty.order": "order is empty",
+	"game.sidebar.order.command_delete": "delete",
 	"game.bottom_tabs.map": "map",
 	"game.bottom_tabs.calc": "calc",
 	"game.bottom_tabs.order": "order",