feat(special-curation): complete implementation with all components

- Database: SpecialSong model with startTime
- Backend: API endpoints for curation
- Admin: Waveform editor and curation page
- Game: startTime support in AudioPlayer
- UI: Curate button in admin dashboard

components/Game.tsx

@@ -16,6 +16,7 @@ interface GameProps {
         title: string;
         artist: string;
         coverImage: string | null;
+        startTime?: number;
     } | null;
     genre?: string | null;
     isSpecial?: boolean;
@@ -195,6 +196,7 @@ export default function Game({ dailyPuzzle, genre = null, isSpecial = false, max
                     <AudioPlayer
                         src={dailyPuzzle.audioUrl}
                         unlockedSeconds={unlockedSeconds}
+                        startTime={dailyPuzzle.startTime}
                         autoPlay={lastAction === 'SKIP'}
                     />
                 </div>