Add client barrel auto-sort functionality to inventoryClient

inventoryClient.lua

@@ -1384,7 +1384,17 @@ local function main()
             end
         end,
 
-        -- Task 4: Touch event listener (both monitors)
+        -- Task 4: Client barrel auto-sort (sends to master)
+        function()
+            if CLIENT_BARREL_NAME == "" then return end
+            print("[OK]   Client barrel: " .. CLIENT_BARREL_NAME)
+            while true do
+                sendToMaster({ type = "sort_barrel", barrelName = CLIENT_BARREL_NAME })
+                sleep(2)
+            end
+        end,
+
+        -- Task 5: Touch event listener (both monitors)
         function()
             while true do
                 local event, side, x, y = os.pullEvent("monitor_touch")