feat(prediction): KOSPS/앙상블 준비중 팝업 + 기본 모델 POSEIDON 변경

- KOSPS 모델 클릭 시 "준비중" alert 팝업
- 앙상블 모델 클릭 시 "준비중" alert 팝업
- 기본 선택 모델을 KOSPS → POSEIDON으로 변경

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

frontend/src/tabs/prediction/components/OilSpillView.tsx

@@ -105,7 +105,7 @@ export function OilSpillView() {
   const [isSelectingLocation, setIsSelectingLocation] = useState(false)
   const [oilTrajectory, setOilTrajectory] = useState<Array<{ lat: number; lon: number; time: number; particle?: number; model?: PredictionModel }>>([])
   const [isRunningSimulation, setIsRunningSimulation] = useState(false)
-  const [selectedModels, setSelectedModels] = useState<Set<PredictionModel>>(new Set(['KOSPS']))
+  const [selectedModels, setSelectedModels] = useState<Set<PredictionModel>>(new Set(['POSEIDON']))
   const [predictionTime, setPredictionTime] = useState(48)
   const [spillType, setSpillType] = useState('연속')
   const [oilType, setOilType] = useState('벙커C유')
@@ -163,7 +163,7 @@ export function OilSpillView() {
   // 분석 탭 초기 진입 시 기본 데모 자동 표시
   useEffect(() => {
     if (activeSubTab === 'analysis' && oilTrajectory.length === 0 && !selectedAnalysis) {
-      const models = Array.from(selectedModels.size > 0 ? selectedModels : new Set<PredictionModel>(['KOSPS']))
+      const models = Array.from(selectedModels.size > 0 ? selectedModels : new Set<PredictionModel>(['POSEIDON']))
       const demoTrajectory = generateDemoTrajectory(incidentCoord, models, predictionTime)
       setOilTrajectory(demoTrajectory)
       const demoBooms = generateAIBoomLines(demoTrajectory, incidentCoord, algorithmSettings)

frontend/src/tabs/prediction/components/PredictionInputSection.tsx

@@ -338,14 +338,18 @@ const PredictionInputSection = ({
           {/* Model Selection (다중 선택) */}
           <div className="flex flex-wrap gap-[3px]">
             {([
-              { id: 'KOSPS' as PredictionModel, color: 'var(--cyan)' },
-              { id: 'POSEIDON' as PredictionModel, color: 'var(--red)' },
-              { id: 'OpenDrift' as PredictionModel, color: 'var(--blue)' },
+              { id: 'KOSPS' as PredictionModel, color: 'var(--cyan)', ready: false },
+              { id: 'POSEIDON' as PredictionModel, color: 'var(--red)', ready: true },
+              { id: 'OpenDrift' as PredictionModel, color: 'var(--blue)', ready: true },
             ] as const).map(m => (
               <div
                 key={m.id}
                 className={`prd-mc ${selectedModels.has(m.id) ? 'on' : ''} cursor-pointer`}
                 onClick={() => {
+                  if (!m.ready) {
+                    alert(`${m.id} 모델은 현재 준비중입니다.`)
+                    return
+                  }
                   const next = new Set(selectedModels)
                   if (next.has(m.id)) {
                     next.delete(m.id)
@@ -362,11 +366,7 @@ const PredictionInputSection = ({
             <div
               className={`prd-mc ${selectedModels.size === ALL_MODELS.length ? 'on' : ''} cursor-pointer`}
               onClick={() => {
-                if (selectedModels.size === ALL_MODELS.length) {
-                  onModelsChange(new Set(['KOSPS']))
-                } else {
-                  onModelsChange(new Set(ALL_MODELS))
-                }
+                alert('앙상블 모델은 현재 준비중입니다.')
               }}
             >
               <span className="prd-md" style={{ background: 'var(--purple)' }} />