Prevent Instant Unequip of Clothing (#594)

# Description
Prevents players from picking up their own equipped clothing (via the
"put in hand" verb or otherwise) and thus bypassing the unequip delay
completely.

Does so by cancelling the GettingPickedUpAttemptEvent on equipped
clothing. This does not prevent unequipping the clothing normally, i.e.
by interacting with it in the inventory, or stripping clothing from
others.

# Changelog
No cl no fun - most people don't even know this was an option.

Content.Shared/Clothing/EntitySystems/ClothingSystem.cs

@@ -9,6 +9,7 @@
 using Content.Shared.Tag;
 using Robust.Shared.GameStates;
 using System.Linq;
+using Robust.Shared.Containers;
 
 namespace Content.Shared.Clothing.EntitySystems;
 
@@ -19,6 +20,7 @@ public abstract class ClothingSystem : EntitySystem
     [Dependency] private readonly TagSystem _tagSystem = default!;
     [Dependency] private readonly InventorySystem _invSystem = default!;
     [Dependency] private readonly SharedHandsSystem _handsSystem = default!;
+    [Dependency] private readonly SharedContainerSystem _containerSys = default!;
 
     [ValidatePrototypeId<TagPrototype>]
     private const string HairTag = "HidesHair";
@@ -36,6 +38,7 @@ public override void Initialize()
         SubscribeLocalEvent<ClothingComponent, GotEquippedEvent>(OnGotEquipped);
         SubscribeLocalEvent<ClothingComponent, GotUnequippedEvent>(OnGotUnequipped);
         SubscribeLocalEvent<ClothingComponent, ItemMaskToggledEvent>(OnMaskToggled);
+        SubscribeLocalEvent<ClothingComponent, GettingPickedUpAttemptEvent>(OnPickedUp);
 
         SubscribeLocalEvent<ClothingComponent, ClothingEquipDoAfterEvent>(OnEquipDoAfter);
         SubscribeLocalEvent<ClothingComponent, ClothingUnequipDoAfterEvent>(OnUnequipDoAfter);
@@ -165,6 +168,18 @@ private void OnMaskToggled(Entity<ClothingComponent> ent, ref ItemMaskToggledEve
         ToggleVisualLayer(args.Wearer, HumanoidVisualLayers.Snout, NoseTag);
     }
 
+    private void OnPickedUp(Entity<ClothingComponent> ent, ref GettingPickedUpAttemptEvent args)
+    {
+        // If this clothing is equipped by the performer of this action, and the clothing has an unequip delay, stop the attempt
+        if (ent.Comp.UnequipDelay <= TimeSpan.Zero
+            || !_invSystem.TryGetContainingSlot(ent.Owner, out var slot)
+            || !_containerSys.TryGetContainingContainer(ent, out var container)
+            || container.Owner != args.User)
+            return;
+
+        args.Cancel();
+    }
+
     private void OnEquipDoAfter(Entity<ClothingComponent> ent, ref ClothingEquipDoAfterEvent args)
     {
         if (args.Handled || args.Cancelled || args.Target is not { } target)