Add weapon acquisition and swapping systems with data handling

GameCore/Player/EquipmentComponent.cs

@@ -0,0 +1,9 @@
+using GameCore.ECS.Interfaces;
+
+namespace GameCore.Player;
+
+public class EquipmentComponent : IComponent
+{
+    public List<string> EquippableWeaponItemIds { get; set; } = [];
+    public int CurrentWeaponIndex { get; set; } = -1; // -1 indicates no weapon equipped
+}