feat(resist): EnemyManager 元素抗性加载+命中查表；enemies.json Fast 种子抗火弱冰

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

scripts/autoloads/enemy_manager.gd

@@ -41,6 +41,8 @@ var _SPEED: Dictionary = {}        # type → 移动速度
 var _ARMOR: Dictionary = {}        # type → 护甲
 var _RENDER_SIZE: Dictionary = {}  # type → 渲染直径
 var _RENDER_COLOR: Dictionary = {} # type → 渲染颜色
+var _RESIST: Dictionary = {}       # type → PackedFloat32Array(6)，index=damage_type，[0]物理恒0
+const _RESIST_ELEMENTS := {"fire": 1, "ice": 2, "lightning": 3, "poison": 4, "arcane": 5}
 
 const ARCHETYPE_JSON: String = "res://data/enemies.json"
 
@@ -61,6 +63,12 @@ func _load_json_archetypes() -> void:
 		_RENDER_SIZE[t] = float(d.get("size", 14.0))
 		var c: Array = d.get("color", [0.9, 0.3, 0.3])
 		_RENDER_COLOR[t] = Color(float(c[0]), float(c[1]), float(c[2]))
+		var rf := PackedFloat32Array([0, 0, 0, 0, 0, 0])
+		var res_d: Dictionary = d.get("resistances", {})
+		for ename in _RESIST_ELEMENTS:
+			if res_d.has(ename):
+				rf[_RESIST_ELEMENTS[ename]] = clampf(float(res_d[ename]), -0.9, 0.9)
+		_RESIST[t] = rf
 
 var _nav_region: NavigationRegion2D = null   # 程序化矩形导航区
 var _pathfinders: Dictionary = {}            # entity_id → {"agent":NavigationAgent2D, "host":Node2D}
@@ -247,6 +255,13 @@ func set_entity_pos(entity_id: int, pos: Vector2) -> void:
 	_data[base + 0] = pos.x
 	_data[base + 1] = pos.y
 
+## 元素抗性查表：越界/缺失回退 0（物理 index 0 恒 0）
+func _resist_for(etype: int, dtype: int) -> float:
+	var rf: PackedFloat32Array = _RESIST.get(etype, PackedFloat32Array())
+	if dtype < 0 or dtype >= rf.size():
+		return 0.0
+	return rf[dtype]
+
 ## S1 完整伤害接口：从 DamageContextPool 取 context，计算公式后扣 HP
 ## 公式（S1 简化）：final_dmg = base_damage * mult
 ## S4 起补充 resistance / armor（参见 combat_mechanics_depth.md §4）
@@ -254,7 +269,12 @@ func apply_damage_from_context(entity_id: int, ctx_id: int) -> bool:
 	var ctx: DamageContext = DamageContextPool.get_context(ctx_id)
 	if ctx == null:
 		return false
-	var final_dmg: float = ctx.calc_damage()
+	var slot: int = _entity_index_map.get(entity_id, -1)
+	var res: float = 0.0
+	if slot >= 0:
+		var etype: int = int(_data[slot * ENEMY_STRIDE + 6])
+		res = _resist_for(etype, ctx.damage_type)
+	var final_dmg: float = ctx.calc_damage(0.0, res)
 	return apply_damage(entity_id, final_dmg, ctx.owner_id, true)
 
 ## 直接扣血接口；source_id 用于击杀归属，record_dps 控制是否计入 DPS