Validate delete/swap kit slots are within 1-9

- Use `parseSlotInRange(..., 1, 9)` in `/deletekit` and `/swapkit`
- Reject out-of-range slot arguments before command execution

Author: rossnoah

src/main/java/dev/noah/perplayerkit/commands/kits/DeleteKitCommand.java

@@ -46,7 +46,7 @@ public boolean onCommand(@NotNull CommandSender sender, @NotNull Command command
             return true;
         }
 
-        Integer slot = SlotArgumentParser.parseSlot(args[0]);
+        Integer slot = SlotArgumentParser.parseSlotInRange(args[0], 1, 9);
         KitManager kitManager = KitManager.get();
         if (slot == null) {
             player.sendMessage(ChatColor.RED + "Usage: /deletekit <slot>");

src/main/java/dev/noah/perplayerkit/commands/kits/SwapKitCommand.java

@@ -46,8 +46,8 @@ public boolean onCommand(@NotNull CommandSender sender, @NotNull Command command
             return true;
         }
 
-        Integer slot1 = SlotArgumentParser.parseSlot(args[0]);
-        Integer slot2 = SlotArgumentParser.parseSlot(args[1]);
+        Integer slot1 = SlotArgumentParser.parseSlotInRange(args[0], 1, 9);
+        Integer slot2 = SlotArgumentParser.parseSlotInRange(args[1], 1, 9);
 
         if (slot1 == null || slot2 == null) {
             player.sendMessage(ChatColor.RED + "Usage: /swapkit <slot1> <slot2>");