Autocast only at the start of battle

[TheKingsRaven]

When playing as an Archmage I like to have Time Shield autocast when enemies are visible, however when I get into a long combat this occasionally results in the shield activating at a bad time.

What I would like is an autocast for when a rest or an auto-explore is interrupted (not counting rest ending because of resources filling up). That signals the start of most battles, so it's the perfect time for an autocast and also covers additional useful cases like when you're interrupted by a trap.