implement a new mode, HIJACK

Author: matsu1213

src/main/java/net/azisaba/lgw/core/LeonGunWar.java

@@ -38,7 +38,7 @@
 import org.bukkit.plugin.PluginManager;
 import org.bukkit.plugin.java.JavaPlugin;
 import org.bukkit.scheduler.BukkitTask;
-import org.jspecify.annotations.Nullable;
+import org.jetbrains.annotations.Nullable;
 import org.slf4j.Logger;
 
 import java.io.IOException;
@@ -79,14 +79,6 @@ public class LeonGunWar extends JavaPlugin {
     private WeaponControlConfig weaponControlConfig;
     private ItemsConfig itemsConfig;
 
-    private final MatchStartCountdown matchStartCountdown = new MatchStartCountdown();
-    private final MapSelectCountdown mapSelectCountdown = new MapSelectCountdown();
-    private final ScoreboardDisplayer scoreboardDisplayer = new ScoreboardDisplayer();
-    private final MatchManager manager = new MatchManager();
-    private final AssistStreaks assistStreaks = new AssistStreaks();
-    private final KillStreaks killStreaks = new KillStreaks();
-    private final TradeBoardManager tradeBoardManager = new TradeBoardManager();
-
     private SQLConnection sqlConnection;
 
     public static JSONMessage getQuickBar() {

src/main/java/net/azisaba/lgw/core/MatchManager.java

@@ -17,10 +17,6 @@
 import net.azisaba.lgw.core.tasks.LeaderSelectionTask;
 import net.azisaba.lgw.core.tasks.MatchCountdownTask;
 import net.azisaba.lgw.core.util.*;
-import net.azisaba.lgw.core.utils.BroadcastUtils;
-import net.azisaba.lgw.core.utils.Chat;
-import net.azisaba.lgw.core.utils.CustomItem;
-import net.azisaba.lgw.core.utils.SecondOfDay;
 import net.azisaba.playersettings.PlayerSettings;
 import net.azisaba.playersettings.util.SettingsData;
 import net.azisaba.lgw.core.util.BattleTeam;

src/main/java/net/azisaba/lgw/core/util/GameMap.java

@@ -4,6 +4,8 @@
 import org.bukkit.Location;
 import org.bukkit.World;
 
+import java.util.ArrayList;
+import java.util.List;
 import java.util.Map;
 
 /**