added AbstractEvent and basic Scoreboard functionality

core/src/main/java/eu/mhsl/craftattack/spawn/core/Main.java

@@ -10,6 +10,7 @@ import org.bukkit.plugin.java.JavaPlugin;
 import org.reflections.Reflections;
 
 import java.lang.reflect.ParameterizedType;
+import java.util.ArrayList;
 import java.util.List;
 import java.util.Set;
 import java.util.logging.Level;
@@ -49,7 +50,7 @@ public final class Main extends JavaPlugin {
         Main.logger().info(String.format("Loaded %d repositories!", this.repositoryLoader.getRepositories().size()));
 
         Main.logger().info("Loading appliances...");
-        this.appliances = this.findSubtypesOf(Appliance.class).stream()
+        this.appliances = new ArrayList<>(this.findSubtypesOf(Appliance.class).stream()
             .filter(applianceClass -> !disabledAppliances.contains(applianceClass.getSimpleName()))
             .filter(appliance -> {
                 Appliance.Flags flags = appliance.getAnnotation(Appliance.Flags.class);
@@ -63,7 +64,7 @@ public final class Main extends JavaPlugin {
                     throw new RuntimeException(String.format("Failed to create instance of '%s'", applianceClass.getName()), e);
                 }
             })
-            .toList();
+            .toList());
         Main.logger().info(String.format("Loaded %d appliances!", this.appliances.size()));
 
         Main.logger().info("Initializing appliances...");