Use new ThreadPoolExecutor to create executor of VT scheduler

This probably can avoid high CPU usage when executing plugin's high frequency tasks

patches/server/0066-Virtual-Thread-for-async-scheduler.patch

@@ -5,10 +5,10 @@ Subject: [PATCH] Virtual Thread for async scheduler
 
 
 diff --git a/src/main/java/org/bukkit/craftbukkit/scheduler/CraftAsyncScheduler.java b/src/main/java/org/bukkit/craftbukkit/scheduler/CraftAsyncScheduler.java
-index 3c1992e212a6d6f1db4d5b807b38d71913619fc0..fe4f1868a5baebceb9ad0520f059ac8c4a68d397 100644
+index 3c1992e212a6d6f1db4d5b807b38d71913619fc0..e9168902552cc6640db3a432dbd9e695f2e3ec9c 100644
 --- a/src/main/java/org/bukkit/craftbukkit/scheduler/CraftAsyncScheduler.java
 +++ b/src/main/java/org/bukkit/craftbukkit/scheduler/CraftAsyncScheduler.java
-@@ -38,17 +38,30 @@ import java.util.concurrent.TimeUnit;
+@@ -38,17 +38,40 @@ import java.util.concurrent.TimeUnit;
 
  public class CraftAsyncScheduler extends CraftScheduler {
 
@@ -28,13 +28,23 @@ index 3c1992e212a6d6f1db4d5b807b38d71913619fc0..fe4f1868a5baebceb9ad0520f059ac8c
 +
 +        // Leaf start - Ability to use Virtual Thread for async scheduler
 +        if (org.dreeam.leaf.config.modules.opt.VT4BukkitScheduler.enabled) {
-+            executor = Executors.newThreadPerTaskExecutor(Thread.ofVirtual().name("Craft Scheduler Thread - ", 0).factory());
++            executor = new ThreadPoolExecutor(
++                    4, Integer.MAX_VALUE, 10L, TimeUnit.SECONDS, new SynchronousQueue<>(), // Use 10s for keepalive time
++                    Thread.ofVirtual()
++                            .name("Craft Scheduler Thread - ", 0)
++                            .uncaughtExceptionHandler(new net.minecraft.DefaultUncaughtExceptionHandlerWithName(net.minecraft.server.MinecraftServer.LOGGER))
++                            .factory()
++            );
++
 +            return;
 +        }
 +
 +        executor = new ThreadPoolExecutor(
 +                4, Integer.MAX_VALUE, 30L, TimeUnit.SECONDS, new SynchronousQueue<>(),
-+                new ThreadFactoryBuilder().setNameFormat("Craft Scheduler Thread - %1$d").setUncaughtExceptionHandler(new net.minecraft.DefaultUncaughtExceptionHandlerWithName(net.minecraft.server.MinecraftServer.LOGGER)).build());
++                new ThreadFactoryBuilder()
++                        .setNameFormat("Craft Scheduler Thread - %1$d")
++                        .setUncaughtExceptionHandler(new net.minecraft.DefaultUncaughtExceptionHandlerWithName(net.minecraft.server.MinecraftServer.LOGGER))
++                        .build());
 +
 +        var threadPoolExecutor = (ThreadPoolExecutor) executor;
 +