Would copper sulfate corrode copper metal over time?
$\ce{CuSO4}$ will not corrode pure copper appreciably over a few months (though there is some dissolution and redeposition through random processes, such as density gradients and thermal motion, it might just reduce a mirror finish to slightly roughened).

However, if the electrodes or wires are brass, bronze or other alloy, or if there are other metals in contact, such as a tin-lead solder joint, there is a chance of some corrosion. In fact, copper sulfate is used to test passivation of stainless steel, and visible corrosion of iron can take place in minutes.