Yeah I don't think there is one.  I looked.  I mean I really looked and found nothing that relates to this.  Its extremely annoying and screws up my camera in tactical battles something bad.

To help you spot idle units, they'll have a thick yellow border on the unit tree on the left hand side. Units that are out of moves won't have the border. I'm actually not sure if that setting also works in tactical battles or not, I have it on and haven't tried turning it off

Which does not work.  Every ranged attack, bows or spells, still has the camera swing.

Actually, that's not true.  Every ranged attack with a moving particle effect has the camera swing.  Sometimes when I cast 'Firebolt', there is no flame, simply '-x' or 'Miss' over the target.  But every attack that has a moving particle effect (arrow or fire trail) will have the 'camera swing'.  And sometimes the start point is off the map, not at the unit.

Thank you! The camera jumping while shooting with bows is really annoying.