Initial set up for item use

PkmnLib.Static/Item.cs

@@ -1,4 +1,5 @@
 using System.Collections.Immutable;
+using PkmnLib.Static.Moves;
 using PkmnLib.Static.Utils;
 
 namespace PkmnLib.Static;
@@ -104,6 +105,9 @@ public interface IItem : INamedValue
     /// A set of arbitrary flags that can be set on the item.
     /// </summary>
     ImmutableHashSet<StringKey> Flags { get; }
+    
+    ISecondaryEffect? Effect { get; }
+    ISecondaryEffect? BattleEffect { get; }
 
     /// <summary>
     /// Checks whether the item has a specific flag.
@@ -118,12 +122,14 @@ public class ItemImpl : IItem
 {
     /// <inheritdoc cref="ItemImpl"/>
     public ItemImpl(StringKey name, ItemCategory category, BattleItemCategory battleCategory, int price,
-        IEnumerable<StringKey> flags)
+        IEnumerable<StringKey> flags, ISecondaryEffect? effect, ISecondaryEffect? battleTriggerEffect)
     {
         Name = name;
         Category = category;
         BattleCategory = battleCategory;
         Price = price;
+        Effect = effect;
+        BattleEffect = battleTriggerEffect;
         Flags = [..flags];
     }
 
@@ -142,6 +148,12 @@ public class ItemImpl : IItem
     /// <inheritdoc />
     public ImmutableHashSet<StringKey> Flags { get; }
 
+    /// <inheritdoc />
+    public ISecondaryEffect? Effect { get; }
+
+    /// <inheritdoc />
+    public ISecondaryEffect? BattleEffect { get; }
+
     /// <inheritdoc />
     public bool HasFlag(string key)
     {