Replace ValidatePrototypeId uses with ProtoId or EntProtoId (#38814)

* The easy ones

* For certain values of easy

* Easy test

* Hair

* Fix sandbox violations

* Sort usings

Content.Shared/Inventory/InventorySystem.Equip.cs

@@ -15,6 +15,7 @@ using Content.Shared.Strip.Components;
 using Content.Shared.Whitelist;
 using Robust.Shared.Audio.Systems;
 using Robust.Shared.Containers;
+using Robust.Shared.Prototypes;
 using Robust.Shared.Timing;
 using Robust.Shared.Utility;
 
@@ -35,8 +36,7 @@ public abstract partial class InventorySystem
     [Dependency] private readonly EntityWhitelistSystem _whitelistSystem = default!;
     [Dependency] private readonly SharedStrippableSystem _strippable = default!;
 
-    [ValidatePrototypeId<ItemSizePrototype>]
-    private const string PocketableItemSize = "Small";
+    private static readonly ProtoId<ItemSizePrototype> PocketableItemSize = "Small";
 
     private void InitializeEquip()
     {