With a rising share of income going to robots (capital) rather than humans (labor), there needs to be a stronger social safety net. This means guaranteed health insurance, health care, retirement benefits, and even a minimum income.
That safety net will have to be paid for via some combination of taxes on wealth, profits, and investment income.
I guess a country could always wage war against another and take their resources or enslave their people.
Is that the ultimate outcome?
Not trying to stir politics here, just to find the theoretical limit of an economy where all actors can be automated.
You are confusing money with wealth (stuff people want). The money would come from the government, which can simply print it.
Take a hypothetical situation where robots cause the total amount of wealth (stuff) created, in one year, to increase by 100%. Now assume the government prints enough money to increase the total amount of money by 100%. In this case, wealth has increased by 100%, and money has increased by 100%, so people's ability to get stuff has increased 100%, with 0% inflation.
In the real world, things never work out so cleanly, but the above offers a simplified model of what could happen.