Is attending (and presenting at) a summit taken as an "honor'' in a CV elevating the chance for tenure-track applications?
I think this strongly depends on the field. 

In pure mathematics, I think nobody would be the slightest impressed by "represented my university in the future research leader summit, which managed to heap 25 nobel laureates into a big pile". It might even have a slightly silly and vain vibe (whereas everyone would be ecstatic about an invited talk at the ICM). 

But this could be completely different in other fields; so I think your best guess is to trust the opinions and reactions of the (senior) colleagues in your field.