feat(mana): 魔力虹吸多来源（Core base + 卡组 meta.mana_leech 求和，换杖重算）

scripts/autoloads/wand_preset.gd

@@ -37,6 +37,7 @@ func _core_from_dict(cid: String, d: Dictionary) -> CoreDefinition:
 	c.edges         = d.get("edges", [])
 	c.base_mana_max   = float(d.get("mana_max", 100.0))
 	c.base_mana_regen = float(d.get("mana_regen", 5.0))
+	c.base_mana_leech = float(d.get("mana_leech", 0.0))
 	return c
 
 ## 默认装备（combat_test 等用）：wand_basic + 第一个 ACTION 法术

scripts/domain/combat/combat_manager.gd

@@ -256,6 +256,11 @@ func _rebuild_wand() -> void:
 			continue
 		nodes.append(SpellRegistry.get_spell(sid))  # 纯数据驱动；未知 id → null（下游按位置跳过）
 	_equipped_compiled = SpellEvaluator.compile_wand(_equipped_core, nodes)
+	var leech: float = _equipped_core.base_mana_leech if _equipped_core else 0.0
+	for n in nodes:
+		if n != null:
+			leech += float(n.meta.get("mana_leech", 0.0))
+	PlayerStats.mana_leech = leech
 
 # ── 法杖存档（ProfileManager A/B 槽，ADR-A2）─────────────────
 func get_wand_save_data() -> Dictionary:

scripts/domain/spell_system/core_definition.gd

@@ -30,3 +30,4 @@ var topology:    int     = Topology.LINEAR
 ## 魔力池（MVP）——由 WandPreset 从 cores.json 读入
 @export var base_mana_max:   float = 100.0
 @export var base_mana_regen: float = 5.0    # 每秒回复
+@export var base_mana_leech: float = 0.0    # 击杀回蓝基础值（可叠加卡组内 meta.mana_leech）