The Space Shuttle was powered by fuel cells rather than solar panels. It could only operate in space as long as it had oxygen and hydrogen available. So there was never an option to "leave one in space" as it could only last a couple weeks at best.
There was a "space tug" concept out of MSFC in the 70s that was basically a capsule with some robot arms mounted on a service module. It would have acted as a repair truck as you say.
It would have also been limited by consumables. Refueling in orbit is a non-trivial problem to solve. As is maintaining an orbital fuel depot. A tug and depot would only be able to service satellites in compatible orbits. So you might need to maintain dozens in orbit to service different orbital planes and altitudes.
There was a "space tug" concept out of MSFC in the 70s that was basically a capsule with some robot arms mounted on a service module. It would have acted as a repair truck as you say.
It would have also been limited by consumables. Refueling in orbit is a non-trivial problem to solve. As is maintaining an orbital fuel depot. A tug and depot would only be able to service satellites in compatible orbits. So you might need to maintain dozens in orbit to service different orbital planes and altitudes.