Can we create character with collision detection?
Something like this:

                    local safe_pos = surface.find_non_colliding_position("character", player.position, 20, 0.5)
                    if safe_pos then
                        player.teleport(safe_pos, surface)
                    end

You will need to figure out the event.

+1

I've been stuck with a full hub inventory a few times now. That limits what you can build since you can only place what's already inside the hub. Freeing up space when you have no spare inserter in the hub for example can be a deadlock of the game.

I was chatting with the author. And I learned that the intended game play is that character should be stuck inside the hub, which is the vanilla experience.
Therefore to get across the challenging scenario you described, you need to throw out items from your hub directly into space. If you can't decon space platforms because of lack of space in hub, then you will need to create a belt route from your hub to the edge of the platform where you can throw out stuff by inserters.