【数据存储】行会基金的流水审计：捐献支出的双本账

---捐献：余额与流水同步写入
function GuildFund.donate(guildId, actor, amount)
    local fund = getguildvar(actor, "GUILD", "fund") or 0
    setguildvar(actor, "GUILD", "fund", fund + amount, 1)
    QF_AppendFundLog(guildId, {
        kind = "donate", by = actor:GetName(),
        amount = amount, after = fund + amount, at = os.time(),
    })
    return true
end

---每日对账：余额重算与存储值比对
function GuildFund.audit(guildId)
    local sum = 0
    for _, row in ipairs(QF_LoadFundLog(guildId)) do
        sum = sum + row.amount
    end
    local stored = getguildvar(actor, "GUILD", "fund") or 0
    if math.abs(sum - stored) > 0 then
        QF_Alarm("基金对账差异 " .. guildId)
        return false
    end
    return true
end