Don't have exact numbers but here is my guesstimate from when I removed one dinette seat and the trifold sofa to install a pair of powered theater seats. Dinette seat 40#s, trifold 70#s. New theater seats probably 140#s.
Have not read any limit for weights in slide out but you theoretically could have 4 people around the dinette table and 2 in the trifold sofa and with the weight of some of us
that could be a good bit of weight. So, unless you plan on installing concrete benches, I don't think you will have a weight issue.
Brian will probably chime in on this one. Would be interesting to really know of any weight limit.