how to add an overhead ceiling fixture to a switched outlet run
You could run a cable from the light fixture to a switched outlet and just put the ceiling light in parallel with the switched outlet and leave the outlet switched for a corded lamp, or you could disconnect the switched cable in the receptacle box so that the switch only operates the the new ceiling fixture.  You'd put in a new receptacle with the metal tab connections intact so the receptacle would be powered without being switchable. This would leave no abandoned wire in the wall. but it might be more difficult to fish a wire to a receptacle low on a wall than to fish into a switch box higher on the wall.

Alternatively, you could run a cable from the ceiling light fixture to a wall box with a switch and this might be easier than working lower on the wall. You would probably want to disconnect the old wire to the receptacle, but you could have the switch control both the overhead light and the receptacle.

The problem with either might be overfilling the box. If either of the boxes is the smaller size, you might have to replace it with a deeper box. Replacing the box will make fishing the wires much easier. I have seen experienced electricians in a team fish into an existing switch box in place, but I have never done it.