fix: OSINT 기사 중복 수집 방지 + MapLibre symbol layer race condition 해소

- OsintCollector: title 기반 24h 중복 체크 추가 (GDELT/Google News)
- ShipLayer: hover를 feature-state로 분리하여 setData 빈도 감소
- ShipLayer: ships-korean-label 조건부 마운트 → visibility 제어로 변경

backend/src/main/java/gc/mda/kcg/collector/osint/OsintCollector.java

@@ -118,6 +118,8 @@ public class OsintCollector {
                 if (articleUrl == null || title == null || title.isBlank()) continue;
 
                 if (osintFeedRepository.existsBySourceAndSourceUrl("gdelt", articleUrl)) continue;
+                if (osintFeedRepository.existsByRegionAndTitleAndCollectedAtAfter(
+                        region, title, Instant.now().minus(24, ChronoUnit.HOURS))) continue;
 
                 String seendate = article.path("seendate").asText(null);
                 Instant publishedAt = parseGdeltDate(seendate);
@@ -182,6 +184,8 @@ public class OsintCollector {
 
                 if (link == null || title == null || title.isBlank()) continue;
                 if (osintFeedRepository.existsBySourceAndSourceUrl(sourceName, link)) continue;
+                if (osintFeedRepository.existsByRegionAndTitleAndCollectedAtAfter(
+                        region, title, Instant.now().minus(24, ChronoUnit.HOURS))) continue;
 
                 Instant publishedAt = parseRssDate(pubDate);
 

backend/src/main/java/gc/mda/kcg/domain/osint/OsintFeedRepository.java

@@ -9,5 +9,7 @@ public interface OsintFeedRepository extends JpaRepository<OsintFeed, Long> {
 
     boolean existsBySourceAndSourceUrl(String source, String sourceUrl);
 
+    boolean existsByRegionAndTitleAndCollectedAtAfter(String region, String title, Instant since);
+
     List<OsintFeed> findByRegionAndCollectedAtAfterOrderByPublishedAtDesc(String region, Instant since);
 }

frontend/src/components/layers/ShipLayer.tsx

@@ -359,6 +359,7 @@ export function ShipLayer({ ships, militaryOnly, koreanOnly, hoveredMmsi, focusM
   const [selectedMmsi, setSelectedMmsi] = useState<string | null>(null);
   const [imageReady, setImageReady] = useState(false);
   const highlightKorean = !!koreanOnly;
+  const prevHoveredRef = useRef<string | null>(null);
 
   // focusMmsi로 외부에서 모달 열기
   useEffect(() => {
@@ -399,7 +400,6 @@ export function ShipLayer({ ships, militaryOnly, koreanOnly, hoveredMmsi, focusM
         isMil: isMilitary(ship.category) ? 1 : 0,
         isKorean: ship.flag === 'KR' ? 1 : 0,
         isCheonghae: ship.mmsi === '440001981' ? 1 : 0,
-        isHovered: ship.mmsi === hoveredMmsi ? 1 : 0,
         heading: ship.heading,
       },
       geometry: {
@@ -408,7 +408,26 @@ export function ShipLayer({ ships, militaryOnly, koreanOnly, hoveredMmsi, focusM
       },
     }));
     return { type: 'FeatureCollection' as const, features };
-  }, [filtered, hoveredMmsi]);
+  }, [filtered]);
+
+  // hoveredMmsi 변경 시 feature-state로 hover 표시 (GeoJSON 재생성 없이)
+  useEffect(() => {
+    if (!map) return;
+    const m = map.getMap();
+    if (!m.getSource('ships-source')) return;
+
+    if (prevHoveredRef.current != null) {
+      try {
+        m.removeFeatureState({ source: 'ships-source', id: prevHoveredRef.current });
+      } catch { /* source not ready */ }
+    }
+    if (hoveredMmsi) {
+      try {
+        m.setFeatureState({ source: 'ships-source', id: hoveredMmsi }, { hovered: true });
+      } catch { /* source not ready */ }
+    }
+    prevHoveredRef.current = hoveredMmsi ?? null;
+  }, [map, hoveredMmsi]);
 
   // Register click and cursor handlers
   useEffect(() => {
@@ -447,12 +466,12 @@ export function ShipLayer({ ships, militaryOnly, koreanOnly, hoveredMmsi, focusM
 
   return (
     <>
-      <Source id="ships-source" type="geojson" data={shipGeoJson}>
+      <Source id="ships-source" type="geojson" data={shipGeoJson} promoteId="mmsi">
         {/* Hovered ship highlight ring */}
         <Layer
           id="ships-hover-ring"
           type="circle"
-          filter={['==', ['get', 'isHovered'], 1]}
+          filter={['boolean', ['feature-state', 'hovered'], false]}
           paint={{
             'circle-radius': 18,
             'circle-color': 'rgba(255, 255, 255, 0.1)',
@@ -474,13 +493,13 @@ export function ShipLayer({ ships, militaryOnly, koreanOnly, hoveredMmsi, focusM
             'circle-stroke-opacity': highlightKorean ? 1 : 0.6,
           }}
         />
-        {/* Korean ship label (only when highlighted) */}
-        {highlightKorean && (
+        {/* Korean ship label — always mounted, visibility으로 제어 */}
         <Layer
           id="ships-korean-label"
           type="symbol"
           filter={['==', ['get', 'isKorean'], 1]}
           layout={{
+            'visibility': highlightKorean ? 'visible' : 'none',
             'text-field': ['get', 'name'],
             'text-size': 9,
             'text-offset': [0, 2.2],
@@ -494,7 +513,6 @@ export function ShipLayer({ ships, militaryOnly, koreanOnly, hoveredMmsi, focusM
             'text-halo-width': 1,
           }}
         />
-        )}
         {/* Main ship triangles */}
         <Layer
           id="ships-triangles"