More abilities, refactor stealing held items

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

@@ -0,0 +1,17 @@
+namespace PkmnLib.Plugin.Gen7.Scripts.Abilities;
+
+/// <summary>
+/// Stakeout is an ability that doubles the damage dealt to Pokémon that have switched in this turn.
+///
+/// <see href="https://bulbapedia.bulbagarden.net/wiki/Stakeout_(Ability)">Bulbapedia - Stakeout</see>
+/// </summary>
+[Script(ScriptCategory.Ability, "stakeout")]
+public class Stakeout : Script
+{
+    /// <inheritdoc />
+    public override void ChangeBasePower(IExecutingMove move, IPokemon target, byte hit, ref ushort basePower)
+    {
+        if (target.BattleData?.SwitchInTurn == move.Battle.CurrentTurnNumber)
+            basePower = basePower.MultiplyOrMax(2);
+    }
+}