feat: 드로그 BT 및 전투 패턴 재구성

- 드로그 BT를 페이즈 전환, 부활 트리거, 가중치 근접 패턴 중심으로 재구성

- 땅 울리기 및 콤보-기본기1_3 패턴/스킬/이펙트를 추가하고 기존 평타 파생 자산을 정리

- 드로그 행동 검증용 PlayMode/Editor 테스트와 관련 런타임 상태 추적을 추가

Assets/_Game/Scripts/AI/WeightedPatternSelector.cs

@@ -0,0 +1,115 @@
+using System;
+using System.Collections.Generic;
+
+using UnityEngine;
+
+using Colosseum.AI.BehaviorActions.Conditions;
+
+namespace Colosseum.AI
+{
+    /// <summary>
+    /// 가중치 기반 패턴 선택 후보를 표현합니다.
+    /// </summary>
+    public readonly struct WeightedPatternCandidate
+    {
+        public WeightedPatternCandidate(BossPatternData pattern, float weight)
+        {
+            Pattern = pattern;
+            Weight = weight;
+        }
+
+        public BossPatternData Pattern { get; }
+
+        public float Weight { get; }
+    }
+
+    /// <summary>
+    /// 준비된 패턴 후보 중 하나를 가중치 기반으로 선택합니다.
+    /// </summary>
+    public static class WeightedPatternSelector
+    {
+        public static bool HasAnyReadyPattern(GameObject owner, IReadOnlyList<WeightedPatternCandidate> candidates)
+        {
+            if (owner == null || candidates == null)
+                return false;
+
+            for (int i = 0; i < candidates.Count; i++)
+            {
+                WeightedPatternCandidate candidate = candidates[i];
+                if (candidate.Pattern == null || candidate.Weight <= 0f)
+                    continue;
+
+                if (PatternReadyHelper.IsPatternReady(owner, candidate.Pattern))
+                    return true;
+            }
+
+            return false;
+        }
+
+        public static bool TrySelectReadyPattern(GameObject owner, IReadOnlyList<WeightedPatternCandidate> candidates, out BossPatternData selectedPattern)
+        {
+            if (owner == null)
+            {
+                selectedPattern = null;
+                return false;
+            }
+
+            return TrySelectPattern(
+                candidates,
+                pattern => PatternReadyHelper.IsPatternReady(owner, pattern),
+                UnityEngine.Random.value,
+                out selectedPattern);
+        }
+
+        public static bool TrySelectPattern(
+            IReadOnlyList<WeightedPatternCandidate> candidates,
+            Predicate<BossPatternData> isPatternReady,
+            float normalizedRoll,
+            out BossPatternData selectedPattern)
+        {
+            selectedPattern = null;
+
+            if (candidates == null || isPatternReady == null)
+                return false;
+
+            List<WeightedPatternCandidate> readyCandidates = new List<WeightedPatternCandidate>(candidates.Count);
+            float totalWeight = 0f;
+
+            for (int i = 0; i < candidates.Count; i++)
+            {
+                WeightedPatternCandidate candidate = candidates[i];
+                if (candidate.Pattern == null || candidate.Weight <= 0f)
+                    continue;
+
+                if (!isPatternReady(candidate.Pattern))
+                    continue;
+
+                readyCandidates.Add(candidate);
+                totalWeight += candidate.Weight;
+            }
+
+            if (readyCandidates.Count == 0 || totalWeight <= 0f)
+                return false;
+
+            float clampedRoll = Mathf.Clamp01(normalizedRoll);
+            float targetWeight = clampedRoll >= 1f
+                ? totalWeight
+                : totalWeight * clampedRoll;
+            float cumulativeWeight = 0f;
+
+            for (int i = 0; i < readyCandidates.Count; i++)
+            {
+                WeightedPatternCandidate candidate = readyCandidates[i];
+                cumulativeWeight += candidate.Weight;
+
+                if (targetWeight < cumulativeWeight || i == readyCandidates.Count - 1)
+                {
+                    selectedPattern = candidate.Pattern;
+                    return true;
+                }
+            }
+
+            return false;
+        }
+    }
+}