trigger priority and response to said triggers mtg
Yes, this is correct.



Rule 117.1b states:


  117.1b A player may activate an activated ability any time they have priority.


And rule 117.3b states:


  117.3b The active player receives priority after a spell or ability (other than a mana ability) resolves.


Based on that, you will receive priority after the first trigger resolves, and may activate Steel Overseer's ability, putting it on the stack. After that resolves and each player passes priority, the Voltaic Servant's ability still on the stack resolves normally, untapping target artifact.