[-] Remove unused functions

src/main/java/icu/samnyan/aqua/sega/chusan/service/GameGachaCardService.java

@@ -28,10 +28,6 @@ public class GameGachaCardService {
         return gameGachaCardRepository.findAll();
     }
 
-    public List<GameGachaCard> getByGachaId(int gachaId) {
-        return gameGachaCardRepository.findAllByGachaId(gachaId);
-    }
-
     public List<GameGachaCard> getRandomCards(int gachaId, int times) {
         List<GameGachaCard> gachaCards = gameGachaCardRepository.findAllByGachaId(gachaId);
         List<GameGachaCard> randomCards = new ArrayList<>();

src/main/java/icu/samnyan/aqua/sega/chusan/service/GameMusicService.java

@@ -42,12 +42,4 @@ public class GameMusicService {
         getAll().forEach(music -> musicMap.put(music.getMusicId(), music));
         return musicMap;
     }
-
-    public Optional<Music> getById(String musicId) {
-        return getById(Integer.parseInt(musicId));
-    }
-
-    public Optional<Music> getById(int musicId) {
-        return gameMusicRepository.findByMusicId(musicId);
-    }
 }

src/main/java/icu/samnyan/aqua/sega/chusan/service/UserGachaService.java

@@ -31,9 +31,4 @@ public class UserGachaService {
     public List<UserGacha> getByUserId(String userId) {
         return userGachaRepository.findByUser_Card_ExtId(Long.parseLong(userId));
     }
-
-    public Optional<UserGacha> getByUserAndGachaId(Chu3UserData user, int gachaId) {
-        return userGachaRepository.findByUserAndGachaId(user, gachaId);
-    }
-
 }