First couple abilities implemented

Plugins/PkmnLib.Plugin.Gen7/Scripts/Abilities/Aftermath.cs

@@ -0,0 +1,33 @@
+namespace PkmnLib.Plugin.Gen7.Scripts.Abilities;
+
+[Script(ScriptCategory.Ability, "aftermath")]
+public class Aftermath : Script
+{
+    private IExecutingMove? _lastAttack;
+
+    /// <inheritdoc />
+    public override void OnIncomingHit(IExecutingMove move, IPokemon target, byte hit)
+    {
+        _lastAttack = move;
+    }
+
+    /// <inheritdoc />
+    public override void OnFaint(IPokemon pokemon, DamageSource source)
+    {
+        if (source != DamageSource.MoveDamage)
+            return;
+        if (_lastAttack is null || !_lastAttack.UseMove.HasFlag("contact"))
+            return;
+        var user = _lastAttack.User;
+        if (!user.IsUsable)
+            return;
+        if (user.BattleData is null)
+            return;
+        EventBatchId eventBatchId = new();
+        user.BattleData.Battle.EventHook.Invoke(new AbilityTriggerEvent(pokemon)
+        {
+            BatchId = eventBatchId,
+        });
+        user.Damage(user.MaxHealth / 4, DamageSource.Misc, eventBatchId);
+    }
+}