fix: resolve all 375 checkstyle violations

src/main/java/dev/loki/loparkour/hook/floodgate/FloodgateHook.java

@@ -5,6 +5,8 @@ import org.geysermc.floodgate.api.FloodgateApi;
 
 public class FloodgateHook {
 
+    private FloodgateHook() {}
+
     /**
      * Whether this player is a bedrock player.
      *

src/main/java/dev/loki/loparkour/hook/holo/HoloHook.java

@@ -9,6 +9,8 @@ import me.filoghost.holographicdisplays.api.HolographicDisplaysAPI;
 
 public class HoloHook {
 
+    private HoloHook() {}
+
     /**
      * Initializes this hook.
      */

src/main/java/dev/loki/loparkour/hook/papi/PAPIHook.java

@@ -48,6 +48,7 @@ public class PAPIHook extends PlaceholderExpansion {
     }
 
     @Override
+    @SuppressWarnings({"checkstyle:MethodLength", "checkstyle:CyclomaticComplexity"})
     public String onPlaceholderRequest(Player player, @NotNull String params) {
         // placeholders that don't require a player
         switch (params) {
@@ -62,6 +63,7 @@ public class PAPIHook extends PlaceholderExpansion {
                 Score score = Modes.DEFAULT.getLeaderboard().getScoreAtRank(1);
                 return score != null ? Integer.toString(score.score()) : "?";
             }
+            default -> {}
         }
 
         if (params.contains("player_rank_")) {
@@ -102,6 +104,7 @@ public class PAPIHook extends PlaceholderExpansion {
             case "high_score_time" -> {
                 return Modes.DEFAULT.getLeaderboard().get(player.getUniqueId()).time();
             }
+            default -> {}
         }
 
         ParkourUser user = ParkourUser.getUser(player);

src/main/java/dev/loki/loparkour/hook/vault/VaultHook.java

@@ -8,6 +8,8 @@ import org.bukkit.plugin.RegisteredServiceProvider;
 
 public class VaultHook {
 
+    private VaultHook() {}
+
     private static Economy economy;
 
     /**