【框架设计】精炼系统：精炼石消耗与属性成长曲线

---精炼：消耗精炼石，属性按百分比成长
function Refine.upgrade(actor, slot)
    local lv = tonumber(getplayvar(actor, 2, "Refine_" .. slot)) or 0
    if lv >= 10 then
        sendmsg(actor, 1, "精炼已达上限")
        return false
    end
    local cost = 3 + lv * 2
    if not checkitemw(actor, "精炼石", cost) then
        sendmsg(actor, 1, "精炼石不足，需要 " .. cost .. " 枚")
        return false
    end
    takeitem(actor, "精炼石", cost, 0, "精炼消耗")
    setplayvar(actor, "HUMAN", "Refine_" .. slot, lv + 1, 1)
    Refine.apply(actor, slot, lv + 1)
    return true
end

---精炼属性：基础攻击的百分比加成
function Refine.apply(actor, slot, lv)
    local baseAtk = actor:GetAttack()
    local pct = lv * 2      -- 每级 +2%
    local bonus = math.floor(baseAtk * pct / 100)
    -- 百分比基数只算基础攻击，不含强化加成
    setplayvar(actor, "HUMAN", "RefineAtk_" .. slot, bonus, 1)
    if lv % 5 == 0 then
        sendmsg(actor, 1, "精炼 " .. lv .. " 级达成，攻击加成 +" .. pct .. "%")
    end
end