feat(lotto): 브리핑 컴포넌트 + CSS

src/pages/lotto/components/briefing/CuratorUsageFooter.jsx

@@ -0,0 +1,17 @@
+import useCuratorUsage from '../../hooks/useCuratorUsage';
+import { estimateCost, fmtUsd, fmtTokens } from './pricing';
+
+export default function CuratorUsageFooter() {
+    const { usage } = useCuratorUsage(30);
+    if (!usage) return null;
+    const cost = estimateCost(usage);
+    return (
+        <div className="curator-usage-footer">
+            <span>최근 30일 큐레이터:</span>
+            <span>{usage.calls}회 호출</span>
+            <span>{fmtTokens(usage.tokens_input + usage.tokens_output)} tokens</span>
+            <span>{fmtUsd(cost)}</span>
+            <span>캐시 {(usage.cache_hit_rate * 100).toFixed(0)}%</span>
+        </div>
+    );
+}