feat: 重构事件总线为可实例化架构并发布 1.3.0

- 新增 IShrinkEventBus、ShrinkEventBusBuilder 与 ShrinkEventBusInstance，支持独立 bus、异常策略、启动开关、类型校验和按 phase 派发
- 新增 SubscribeEvent 可释放订阅句柄与订阅快照接口，保留 EventBus 静态门面并委托到默认实例
- 重构监听列表为父子事件链共享锁与快照缓存，支持父事件监听子事件、跨父子数字优先级归并和防御性快照拷贝
- 优化 EventBase 元数据缓存、懒生成 EventId、派发快照挂接与对象池双重归还保护，移除旧 EventCache 热路径
- 恢复本地 ILPostProcessor 兜底并生成静态订阅注册表，避免共享 CodeGen 覆盖外程序集自动注册失效
- 改进事件查看器、Benchmark、README 与 CHANGELOG，并新增 Dispatch/Priority/Registration/Subscription 测试覆盖核心行为

BREAKING CHANGE: 移除 EventBase.GetListenerList()，int 数字优先级重载不再提供默认值，数字优先级 0 现在映射为 NORMAL。

Runtime/IShrinkEventBus.cs

@@ -0,0 +1,109 @@
+using System;
+using System.Collections.Generic;
+using System.Reflection;
+using Cysharp.Threading.Tasks;
+
+namespace ShrinkEventBus
+{
+    public interface IShrinkEventSubscription : IDisposable
+    {
+        long SubscriptionId { get; }
+        bool IsDisposed { get; }
+    }
+
+    public readonly struct ShrinkEventSubscriptionSnapshot
+    {
+        public ShrinkEventSubscriptionSnapshot(long subscriptionId, Type eventType, EventPriority priority,
+            int numericPriority, bool receiveCanceled, object target, string targetTypeName, string methodName,
+            string debugInfo, DateTime registeredAtUtc)
+        {
+            SubscriptionId = subscriptionId;
+            EventType = eventType ?? throw new ArgumentNullException(nameof(eventType));
+            Priority = priority;
+            NumericPriority = numericPriority;
+            ReceiveCanceled = receiveCanceled;
+            Target = target;
+            TargetTypeName = targetTypeName ?? string.Empty;
+            MethodName = methodName ?? string.Empty;
+            DebugInfo = debugInfo ?? string.Empty;
+            RegisteredAtUtc = registeredAtUtc;
+        }
+
+        public long SubscriptionId { get; }
+        public Type EventType { get; }
+        public EventPriority Priority { get; }
+        public int NumericPriority { get; }
+        public bool ReceiveCanceled { get; }
+        public object Target { get; }
+        public string TargetTypeName { get; }
+        public string MethodName { get; }
+        public string DebugInfo { get; }
+        public DateTime RegisteredAtUtc { get; }
+        public bool IsStaticHandler => Target == null;
+    }
+
+    public interface IShrinkEventBus
+    {
+        event Action<EventBase, Type> OnEventTriggered;
+
+#if UNITY_EDITOR
+        event Action<EventBase, string, string, EventHandlerInfo[]> OnEventTriggeredForEditor;
+        bool EnableDebugRecord { get; set; }
+#endif
+
+        bool IsStarted { get; }
+
+        void Start();
+        void AutoRegister(object target);
+        void Register(object target);
+        void Unregister(object target);
+
+        void RegisterEvent<TEvent>(Action<TEvent> handler, EventPriority priority = EventPriority.NORMAL,
+            bool receiveCanceled = false) where TEvent : EventBase;
+        void RegisterEvent<TEvent>(Action<TEvent> handler, int priority) where TEvent : EventBase;
+        void RegisterEvent<TEvent>(Func<TEvent, UniTask> handler, EventPriority priority = EventPriority.NORMAL,
+            bool receiveCanceled = false) where TEvent : EventBase;
+        void RegisterEvent<TEvent>(Func<TEvent, UniTask> handler, int priority) where TEvent : EventBase;
+        IShrinkEventSubscription SubscribeEvent<TEvent>(Action<TEvent> handler,
+            EventPriority priority = EventPriority.NORMAL, bool receiveCanceled = false) where TEvent : EventBase;
+        IShrinkEventSubscription SubscribeEvent<TEvent>(Action<TEvent> handler, int priority)
+            where TEvent : EventBase;
+        IShrinkEventSubscription SubscribeEvent<TEvent>(Func<TEvent, UniTask> handler,
+            EventPriority priority = EventPriority.NORMAL, bool receiveCanceled = false) where TEvent : EventBase;
+        IShrinkEventSubscription SubscribeEvent<TEvent>(Func<TEvent, UniTask> handler, int priority)
+            where TEvent : EventBase;
+
+        void UnregisterEvent<TEvent>(Action<TEvent> handler) where TEvent : EventBase;
+        void UnregisterEvent<TEvent>(Func<TEvent, UniTask> handler) where TEvent : EventBase;
+        void ClearAllSubscribersForEvent<TEvent>() where TEvent : EventBase;
+        void UnregisterAllEventsForObject(object targetObject);
+        void UnregisterAllEvents();
+
+        bool TriggerEvent<TEvent>(TEvent eventArgs) where TEvent : EventBase;
+        bool TriggerEvent<TEvent>(EventPriority phase, TEvent eventArgs) where TEvent : EventBase;
+        UniTask<bool> TriggerEventAsync<TEvent>(TEvent eventArgs) where TEvent : EventBase;
+        UniTask<bool> TriggerEventAsync<TEvent>(EventPriority phase, TEvent eventArgs) where TEvent : EventBase;
+
+        EventHandlerInfo[] GetEventSubscribers<TEvent>() where TEvent : EventBase;
+        ListenerList GetListenerList<TEvent>() where TEvent : EventBase;
+        IReadOnlyDictionary<Type, EventHandlerInfo[]> GetAllSubscribersSnapshot();
+        IReadOnlyList<ShrinkEventSubscriptionSnapshot> GetActiveSubscriptionsSnapshot();
+
+        bool IsInstanceRegistered(object target);
+        int GetRegisteredInstanceCount();
+        int GetRegisteredEventTypeCount();
+    }
+
+    public interface IShrinkEventExceptionHandler
+    {
+        void HandleException(IShrinkEventBus bus, EventBase eventArgs, EventHandlerInfo[] listeners, int index,
+            Exception exception);
+    }
+
+    public enum ShrinkEventExceptionHandlingMode
+    {
+        LogAndContinue,
+        Throw,
+        LogAndThrow
+    }
+}