feat(lotto): DecisionCard 하위 컴포넌트(Pick/Tier/Toggle/Retro) + 스타일

src/pages/lotto/components/decision/TierSection.jsx

@@ -0,0 +1,25 @@
+import PickCard from './PickCard';
+
+const TIER_TITLE = {
+    core: '코어 (필수, 5세트)',
+    bonus: '보너스 (+5)',
+    extended: '확장 (+5)',
+    pool: '풀 (+5)',
+};
+
+export default function TierSection({ tier, picks, rationale, indexBase = 0, totalSets }) {
+    if (!picks?.length) return null;
+    return (
+        <section className={`lc-tier lc-tier--${tier}`}>
+            <header className="lc-tier__head">
+                <h4>{TIER_TITLE[tier]}</h4>
+                {rationale && tier !== 'core' && (
+                    <p className="lc-tier__rationale">{rationale}</p>
+                )}
+            </header>
+            {picks.map((p, i) => (
+                <PickCard key={i} pick={p} index={indexBase + i} total={totalSets} />
+            ))}
+        </section>
+    );
+}