Self-Heal buildup remains even after unit reaches full health

[dzfischer]

Could force self-heal to turn off if at full health and receiving no net static damage/turn (terrain, city defenses).

AI units, including animals, often end up maintaining Self-Heal buildups even while at full health. This is most often seen with melee units that have no other more useful buildups to auto-pick. Self-Heal has a malus to strength, which makes sense as a trade-off, but as a result some full-health units fight with lowered strength in the hands of the AI due to its poor buildup choice. I suggest having all AI-controlled units dismiss their Self-Heal buildup if they are already at full health at the start of their turn.