feat: 项目初始化 + 3D方块世界原型 + AI助搭系统

初始化 monorepo: Go后端(7微服务) + Unity客户端(9模块) + 启动器

HTML5原型: Three.js 3D体素世界, Perlin噪声地形, 原版材质, 22种方块

Minecraft创造模式背包: 双栏布局, 拖拽移动物品, 方向性元件引脚

AI助搭策划文档 + 客户端/服务端骨架 + Docker Compose + CI

launcher/PCL-CE/PCL.Core/Utils/Threading/LimitedTaskPool.cs

@@ -0,0 +1,57 @@
+using System;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace PCL.Core.Utils.Threading;
+
+// Partly generated by o4-mini-high (20250709)
+
+/// <summary>
+/// 可限制并发线程数量的任务池。
+/// </summary>
+public class LimitedTaskPool
+{
+    /// <summary>
+    /// 最大并发线程数。
+    /// </summary>
+    public int MaxThread { get; }
+
+    private readonly TaskFactory _factory;
+    private readonly CancellationTokenSource _cts = new();
+
+    /// <summary>
+    /// 初始化 <see cref="LimitedTaskPool"/> 实例
+    /// </summary>
+    /// <param name="maxThread">参考 <see cref="MaxThread"/>，最小为 1</param>
+    /// <exception cref="ArgumentOutOfRangeException"><paramref name="maxThread"/> 小于 1</exception>
+    public LimitedTaskPool(int maxThread)
+    {
+        if (maxThread < 1) throw new ArgumentOutOfRangeException(nameof(maxThread));
+
+        MaxThread = maxThread;
+
+        var scheduler = new LimitedConcurrencyLevelTaskScheduler(maxThread);
+        var cancellationToken = _cts.Token;
+
+        _factory = new TaskFactory(
+            cancellationToken,
+            TaskCreationOptions.DenyChildAttach,
+            TaskContinuationOptions.None,
+            scheduler);
+    }
+
+    /// <summary>
+    /// 提交一个任务。
+    /// </summary>
+    public Task Submit(Action work) => _factory.StartNew(work);
+
+    /// <summary>
+    /// 提交一个异步任务。
+    /// </summary>
+    public Task Submit(Func<Task> work) => _factory.StartNew(work).Unwrap();
+
+    /// <summary>
+    /// 取消所有任务。
+    /// </summary>
+    public void CancelAll() => _cts.Cancel();
+}