Reset inactivity timer when an attack is blocked

[Kip]

One thing worth noting is that prep time does not count toward inactivity.  If you repair your shield before toming so you can pick it up after, for instance, that is a valid way of proving your presence.

I would be fine with considering more ways of indicating presence but those ways cannot be so easily abused as to negate the entire system for a certain class of characters.  Counting shield damage, in my opinion, would entirely negate the system for shielders and is not a valid way of testing for presence.