It isn't commercial labor when an adult does their own chores (I think), as it's more related to the people in a household maintaining their own home. It likely wouldn't be labor for a child for the same reasons, though I'm not sure.
But it could start to look like labor when it's something that produces commercial value, for example, it's more like a 'chore' to water the vegetable garden in the backyard, but it's more like 'labor' to tend to 20 acres of farmland.
Excessive chores, though, could be prevented under child abuse law rather than child labor law, depending on how it's enforced. Doing all the household work voluntarily for no reason other than it's fun? Almost certainly legal. No video games until you clean the dishes? Probably legal. No food until you sweep, mop, dust, and shine every surface in the house? Probably abuse.