feat(enemy): ApproachAttackEngagement——攻击改为起手即打完，不中途收招

寻路逼近↔到射程选招攻击的交战模块。招式射程/冷却/权重归 EnemyAttackSelector，
本模块只决定何时逼近、何时出手。

有意的行为变更：Attack 态去掉 leftAllZones 边，玩家在前摇中跑出感知区不再
中途打断招式，招式完整打完后经 Approach 自然脱战。

Assets/Tests/EditMode/AI/ApproachAttackEngagementTests.cs

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+using NUnit.Framework;
+using BaseGames.AI;
+using BaseGames.Enemies;
+
+namespace BaseGames.Tests.EditMode.AI
+{
+    public class ApproachAttackEngagementTests
+    {
+        const string Rest = "Rest";
+
+        static AiRuntime RunAlone(FakeAiContext ctx)
+        {
+            var m = new ApproachAttackEngagement();
+            var b = new BrainBuilder();
+            AiStateFragments.Locomotion(b, Rest, LocomotionMode.Patrol);
+            m.Build(b, Rest);
+            b.Entry(m.EntryState);
+            return new AiRuntime(b.Build(), ctx);
+        }
+
+        [Test]
+        public void Approach_PursuesLastKnown()
+        {
+            var ctx = new FakeAiContext();
+            ctx.S.Chase = true;
+            ctx.S.Last = new UnityEngine.Vector2(5f, 1f);
+            RunAlone(ctx);
+            Assert.AreEqual(new UnityEngine.Vector2(5f, 1f), ctx.L.PursuedTo);
+        }
+
+        [Test]
+        public void Approach_ToAttack_WhenEligibleAttackExists()
+        {
+            var ctx = new FakeAiContext();
+            ctx.S.Chase = true;
+            var rt = RunAlone(ctx);
+            Assert.AreEqual(ApproachAttackEngagement.Approach, rt.CurrentStateName);
+            ctx.C.Eligible = true;
+            rt.Tick(0.1f);
+            Assert.AreEqual(ApproachAttackEngagement.Attack, rt.CurrentStateName);
+            CollectionAssert.Contains(ctx.C.Used, "best");
+        }
+
+        [Test]
+        public void Attack_BackToApproach_WhenAbilityDone()
+        {
+            var ctx = new FakeAiContext();
+            ctx.S.Chase = true; ctx.C.Eligible = true;
+            var rt = RunAlone(ctx);
+            rt.Tick(0.1f);
+            Assert.AreEqual(ApproachAttackEngagement.Attack, rt.CurrentStateName);
+            ctx.C.Running = null;                 // 招式打完
+            rt.Tick(0.1f);
+            Assert.AreEqual(ApproachAttackEngagement.Approach, rt.CurrentStateName);
+        }
+
+        [Test]
+        public void Approach_ExitsToRest_WhenAllZonesLost()
+        {
+            var ctx = new FakeAiContext();
+            ctx.S.Chase = true;
+            var rt = RunAlone(ctx);
+            ctx.S.Chase = false; ctx.S.Vision = false;
+            rt.Tick(0.1f);
+            Assert.AreEqual(Rest, rt.CurrentStateName);
+        }
+
+        // 有意的行为变更：攻击起手后打完，不中途收招
+        [Test]
+        public void Attack_CompletesEvenWhenPlayerLeavesAllZones()
+        {
+            var ctx = new FakeAiContext();
+            ctx.S.Chase = true; ctx.C.Eligible = true;
+            var rt = RunAlone(ctx);
+            rt.Tick(0.1f);
+            Assert.AreEqual(ApproachAttackEngagement.Attack, rt.CurrentStateName);
+
+            ctx.S.Chase = false; ctx.S.Vision = false;   // 前摇中玩家跑掉
+            rt.Tick(0.1f);
+            Assert.AreEqual(ApproachAttackEngagement.Attack, rt.CurrentStateName); // 不中途收招
+
+            ctx.C.Running = null;                         // 招式打完
+            rt.Tick(0.1f);
+            Assert.AreEqual(ApproachAttackEngagement.Approach, rt.CurrentStateName);
+            rt.Tick(0.1f);
+            Assert.AreEqual(Rest, rt.CurrentStateName);   // 再经 Approach 自然脱战
+        }
+    }
+}

Assets/Tests/EditMode/AI/ApproachAttackEngagementTests.cs.meta

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Assets/_Game/Scripts/Enemies/AIBrain/Modules/Engagement/ApproachAttackEngagement.cs

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+using System;
+using BaseGames.AI;
+
+namespace BaseGames.Enemies
+{
+    /// <summary>
+    /// 寻路逼近 ↔ 到射程选招攻击。招式的射程 / 冷却 / 权重由 EnemyAttackSelector 负责，
+    /// 本模块只决定"什么时候该逼近、什么时候该出手"。
+    /// </summary>
+    [Serializable]
+    public sealed class ApproachAttackEngagement : IEngagementModule
+    {
+        public const string Approach = "Approach";
+        public const string Attack   = "Attack";
+
+        static readonly Func<IAiContext, bool> InChaseZone = x => x.Sensor.InChaseZone();
+
+        public string EntryState => Approach;
+        public Func<IAiContext, bool> CanEngage => InChaseZone;
+        public string EngageLabel => "InChaseZone";
+
+        public void Build(BrainBuilder b, string rest)
+        {
+            b.DeclareState(Approach)
+                .OnEnter(x => x.Locomotion.Pursue(x.Sensor.LastKnown))
+                .Tick  (x => x.Locomotion.Pursue(x.Sensor.LastKnown))
+                .OnExit(x => x.Locomotion.Stop())
+                // 脱战边放在前面：脱战判定优先于是否有合格攻击，避免"已经脱离全部感知区，
+                // 却因为攻击选择器还没来得及清掉合格标记"而卡在交战里出不去。
+                .To(rest)  .When(AiStateFragments.LostAllZones, "leftAllZones")
+                .To(Attack).When(x => x.Combat.HasEligibleAttack(), "attackInRange");
+
+            // 攻击一旦起手就打完：刻意不挂 leftAllZones 边。
+            // 玩家在前摇中跑出感知区时招式仍完整打完，之后经 Approach 自然脱战——
+            // 只多一帧，且消除了"起手到一半凭空收招"的观感缺陷。
+            b.DeclareState(Attack)
+                .OnEnter(x => { x.Locomotion.Stop(); x.Combat.UseBestAttack(); })
+                .OnExit (x => x.Combat.InterruptAbilities())
+                .To(Approach).When(x => !x.Combat.IsAbilityRunning(), "attackDone");
+        }
+    }
+}

Assets/_Game/Scripts/Enemies/AIBrain/Modules/Engagement/ApproachAttackEngagement.cs.meta

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