More abilities, refactor custom triggers to be typed.

Plugins/PkmnLib.Plugin.Gen7/Scripts/Moves/HealPercent.cs

@@ -19,6 +19,10 @@ public class HealPercent : Script
     /// <inheritdoc />
     public override void OnSecondaryEffect(IExecutingMove move, IPokemon target, byte hit)
     {
-        target.Heal((uint)(move.User.BoostedStats.Hp * _healPercent));
+        var args = new CustomTriggers.ModifyHealPercentArgs(move, target, hit, _healPercent);
+        move.RunScriptHook(x => x.CustomTrigger(CustomTriggers.ModifyHealPercent, args));
+        var healPercent = args.HealPercent;
+
+        target.Heal(target.BoostedStats.Hp.MultiplyOrMax(healPercent));
     }
 }