refactor: extract components from SpireTab.tsx to reduce below 400 lines

src/components/game/tabs/index.ts

@@ -13,3 +13,11 @@ export { DebugTab } from './DebugTab';
 export { LootTab } from './LootTab';
 export { AchievementsTab } from './AchievementsTab';
 export { GolemancyTab } from './GolemancyTab';
+
+// Spire sub-components
+export { SpireHeader } from './SpireHeader';
+export { GuardianPanel } from './GuardianPanel';
+export { RoomDisplay } from './RoomDisplay';
+export { FloorControls } from './FloorControls';
+export { CombatStatsPanel } from './CombatStatsPanel';
+export { ActivityLog } from './ActivityLog';