【网络通信】会话保持：网关切换时的会话迁移

local function packSession(actor)
    local p = class(actor)
    local pkg = p:GetName() .. "|" .. (getplayvar(actor, "HUMAN", "NET_LEVEL") or "1") .. "|" .. os.time()
    setsysvarex("SESSION_" .. p:GetName(), pkg, 1)
    return pkg
end

local function restoreSession(actor, pkg)
    local p = class(actor)
    local saved = getsysvar("SESSION_" .. p:GetName()) or ""
    if saved == "" or saved ~= pkg then
        sendmsg(actor, 0, "会话校验未通过，请重新登录")
        return false
    end
    local ts = tonumber(string.match(pkg, "|(%d+)$") or "0")
    if os.time() - ts > 60 then
        sendmsg(actor, 0, "会话迁移超时，请重新登录")
        return false
    end
    setsysvarex("SESSION_" .. p:GetName(), "", 1)
    return true
end