伤害飘字：数字合并与暴击分层

-- 错误：一段伤害飘一个字，满屏数字糊脸
function onDamage(target, value)
    spawnFloat(target, value)
end

local buckets = {}
local function pushDamage(targetId, value, crit)
    local key = targetId .. (crit and "_c" or "_n")
    local b = buckets[key]
    if b == nil then
        b = {value = value}
        buckets[key] = b
        later(0.5, function()
            showFloat(targetId, b.value, crit)
            buckets[key] = nil
        end)
    else
        b.value = b.value + value
    end
end