坐骑合成：碎片集齐必出品质保底

-- 错误：失败扣光碎片，纯随机无保底
function synMount(p)
    setplayvar(p, "mfrag", 0)
    giveMount(p, math.random(1, 4))
end

local NEED = 30
local function synMount(p)
    local n = getplayvar(p, "mfrag") or 0
    if n < NEED then
        sendmsg(p, 1, "碎片 " .. n .. "/" .. NEED)
        return
    end
    setplayvar(p, "mfrag", n - NEED)
    local miss = getplayvar(p, "mMiss") or 0
    local quality
    if miss >= 3 then
        quality = 3
    else
        quality = math.random(1, 4)
    end
    if quality < 3 then
        setplayvar(p, "mMiss", miss + 1)
    else
        setplayvar(p, "mMiss", 0)
    end
    giveMount(p, quality)
end