"The reports" are that 12 were killed total, not that 12 civilians were killed. Only 2 of the killed were civilians as far as I can tell. Several of those who people on Twitter tried to claim were civilians, including a doctor, were admitted by Hezbollah to be Hezbollah members and given Hezbollah funerals.

I've never heard of "42 targets", and given 12 people died total, obviously 42 targets were not killed.

You should provide some sourcing for your numbers.

Targeted attacks against military/militia leadership is not terrorism - almost by definition.

If it was just random devices exploding, then sure, that could be considered terrorism. But it wasn't random devices, it was communication devices procured by Hezbollah and directly given by Hezbollah to their own members for their own purposes.