好友上限：好友位扩展与清理工具

local BASE_CAP = 50
local function addFriend(p, name)
    local friends = getplayvar(p, "FRIENDS") or ""
    if ("|" .. friends .. "|"):find("|" .. name .. "|", 1, true) then
        sendmsg(p, 1, "已是好友")
        return
    end
    local n = 1
    for _ in friends:gmatch("[^|]+") do n = n + 1 end
    local cap = BASE_CAP + (getplayvar(p, "friendExt") or 0)
    if n >= cap then
        sendmsg(p, 1, "好友位已满 " .. n .. "/" .. cap .. "，可扩展或清理")
        return
    end
    setplayvar(p, "FRIENDS", friends .. name .. "|")
    sendmsg(p, 1, "已添加好友 " .. name)
end

local OFFLINE_DAYS = 30
local function cleanFriends(p)
    local friends = getplayvar(p, "FRIENDS") or ""
    local keep, removed = "", 0
    for name in friends:gmatch("[^|]+") do
        local last = tonumber(getsysvar("seen_" .. name) or "0")
        local stale = last == 0
            or (os.time() - last > OFFLINE_DAYS * 86400)
        if stale then
            removed = removed + 1
        else
            keep = keep .. name .. "|"
        end
    end
    setplayvar(p, "FRIENDS", keep)
    sendmsg(p, 1, "清理完成，移除 " .. removed .. " 人")
end