feat: 드로그 공통 보스 BT 프레임워크 정리

- 보스 공통 전투 컨텍스트와 패턴 역할 기반 BT 액션을 추가
- 드로그 패턴 선택을 다운 추가타, 도약, 기본 및 보조 패턴 우선순위 브랜치로 이관
- BT_Drog authoring 그래프를 공통 구조에 맞게 재구성
- 드로그 전용 BT 헬퍼를 정리하고 공통 베이스 액션으로 통합
- 플레이 검증으로 도약, 기본 패턴, 내려찍기, 다운 추가타 루프를 확인

Assets/_Game/Scripts/AI/BehaviorActions/Actions/SelectTargetByDistanceAction.cs

@@ -0,0 +1,172 @@
+using System;
+
+using Unity.Behavior;
+using Unity.Properties;
+using UnityEngine;
+
+using Colosseum;
+using Colosseum.Combat;
+using Colosseum.Enemy;
+
+using Action = Unity.Behavior.Action;
+
+/// <summary>
+/// 거리 조건에 맞는 대상을 선택하는 Behavior Action입니다.
+/// 가장 가까운 대상, 가장 먼 대상, 후보 중 랜덤 선택을 지원합니다.
+/// </summary>
+[Serializable]
+public enum DistanceTargetSelectionMode
+{
+    Nearest = 0,
+    Farthest = 1,
+    Random = 2,
+}
+
+[Serializable, GeneratePropertyBag]
+[NodeDescription(
+    name: "Select Target By Distance",
+    story: "[Tag] 대상 중 [MinRange] 이상 [MaxRange] 이하 범위에서 [SelectionMode] 방식으로 [Target] 선택",
+    category: "Action",
+    id: "4f6a830df3ff4ff5bf8bd2c8b433aa41")]
+public partial class SelectTargetByDistanceAction : Action
+{
+    [SerializeReference]
+    public BlackboardVariable<GameObject> Target;
+
+    [SerializeReference]
+    public BlackboardVariable<string> Tag = new BlackboardVariable<string>("Player");
+
+    [SerializeReference]
+    public BlackboardVariable<float> MinRange = new BlackboardVariable<float>(0f);
+
+    [SerializeReference]
+    public BlackboardVariable<float> MaxRange = new BlackboardVariable<float>(20f);
+
+    [SerializeReference]
+    public BlackboardVariable<DistanceTargetSelectionMode> SelectionMode =
+        new BlackboardVariable<DistanceTargetSelectionMode>(DistanceTargetSelectionMode.Farthest);
+
+    protected override Status OnStart()
+    {
+        if (string.IsNullOrEmpty(Tag.Value))
+            return Status.Failure;
+
+        GameObject[] candidates = GameObject.FindGameObjectsWithTag(Tag.Value);
+        if (candidates == null || candidates.Length == 0)
+            return Status.Failure;
+
+        float minRange = Mathf.Max(0f, MinRange.Value);
+        float maxRange = Mathf.Max(minRange, MaxRange.Value);
+        BossCombatBehaviorContext context = GameObject.GetComponent<BossCombatBehaviorContext>();
+
+        if (minRange <= 0f && context != null)
+            minRange = context.MobilityTriggerDistance;
+
+        if (maxRange <= minRange)
+        {
+            EnemyBase enemyBase = GameObject.GetComponent<EnemyBase>();
+            maxRange = enemyBase != null && enemyBase.Data != null ? enemyBase.Data.AggroRange : 20f;
+        }
+
+        GameObject selectedTarget = SelectionMode.Value switch
+        {
+            DistanceTargetSelectionMode.Nearest => FindNearestTarget(candidates, minRange, maxRange),
+            DistanceTargetSelectionMode.Random => FindRandomTarget(candidates, minRange, maxRange),
+            _ => FindFarthestTarget(candidates, minRange, maxRange),
+        };
+
+        if (selectedTarget == null)
+            return Status.Failure;
+
+        Target.Value = selectedTarget;
+        return Status.Success;
+    }
+
+    private GameObject FindNearestTarget(GameObject[] candidates, float minRange, float maxRange)
+    {
+        GameObject bestTarget = null;
+        float bestDistance = float.MaxValue;
+
+        for (int i = 0; i < candidates.Length; i++)
+        {
+            GameObject candidate = candidates[i];
+            if (!IsValidTarget(candidate, minRange, maxRange, out float distance))
+                continue;
+
+            if (distance >= bestDistance)
+                continue;
+
+            bestDistance = distance;
+            bestTarget = candidate;
+        }
+
+        return bestTarget;
+    }
+
+    private GameObject FindFarthestTarget(GameObject[] candidates, float minRange, float maxRange)
+    {
+        GameObject bestTarget = null;
+        float bestDistance = minRange;
+
+        for (int i = 0; i < candidates.Length; i++)
+        {
+            GameObject candidate = candidates[i];
+            if (!IsValidTarget(candidate, minRange, maxRange, out float distance))
+                continue;
+
+            if (distance <= bestDistance)
+                continue;
+
+            bestDistance = distance;
+            bestTarget = candidate;
+        }
+
+        return bestTarget;
+    }
+
+    private GameObject FindRandomTarget(GameObject[] candidates, float minRange, float maxRange)
+    {
+        System.Collections.Generic.List<GameObject> validTargets = new System.Collections.Generic.List<GameObject>();
+
+        for (int i = 0; i < candidates.Length; i++)
+        {
+            GameObject candidate = candidates[i];
+            if (!IsValidTarget(candidate, minRange, maxRange, out _))
+                continue;
+
+            validTargets.Add(candidate);
+        }
+
+        if (validTargets.Count == 0)
+            return null;
+
+        int randomIndex = UnityEngine.Random.Range(0, validTargets.Count);
+        return validTargets[randomIndex];
+    }
+
+    private bool IsValidTarget(GameObject candidate, float minRange, float maxRange, out float distance)
+    {
+        distance = 0f;
+
+        if (candidate == null || !candidate.activeInHierarchy)
+            return false;
+
+        if (Team.IsSameTeam(GameObject, candidate))
+            return false;
+
+        IDamageable damageable = candidate.GetComponent<IDamageable>();
+        if (damageable != null && damageable.IsDead)
+            return false;
+
+        EnemyBase enemyBase = GameObject.GetComponent<EnemyBase>();
+        float sightRange = enemyBase != null && enemyBase.Data != null
+            ? enemyBase.Data.AggroRange
+            : maxRange;
+
+        distance = Vector3.Distance(GameObject.transform.position, candidate.transform.position);
+        if (distance < minRange || distance > maxRange || distance > sightRange)
+            return false;
+
+        return true;
+    }
+}