Most of the existing actions are game actions (they control the player character)
so they live in actions.game. Eventually, there will be modules for different
kinds of actions that only apply to, e.g. modal UI.
Instead of counting turns, count clock ticks. A WaitAction adds 10 ticks to the
passive healing clock and a WalkAction adds 5. So, you will heal while walking
but at a slower rate.
