add listener and remove memory inventory service

cmd/inventory/main.go

@@ -3,6 +3,7 @@ package main
 import (
 	"context"
 	"log"
+	"time"
 
 	"git.tornberg.me/go-cart-actor/pkg/inventory"
 	"github.com/redis/go-redis/v9"
@@ -24,6 +25,18 @@ func main() {
 		log.Fatalf("Unable to connect to inventory redis: %v", err)
 		return
 	}
+
+	// Start inventory change listener
+	listener := inventory.NewInventoryChangeListener(rdb, ctx, func(changes []inventory.InventoryChange) {
+		for _, change := range changes {
+			log.Printf("Inventory change detected: SKU %s at location %s now has %d", change.SKU, change.StockLocationID, change.Value)
+		}
+	})
+	log.Println("Starting inventory change listener...")
+	go listener.Start()
+	listener.WaitReady()
+	log.Println("Listener is ready, proceeding with inventory operations...")
+
 	rdb.Pipelined(ctx, func(p redis.Pipeliner) error {
 		s.UpdateInventory(p, "1", "1", 10)
 		s.UpdateInventory(p, "2", "2", 20)
@@ -51,4 +64,6 @@ func main() {
 	}
 	log.Printf("Inventory after reservation: %v", v)
 
+	// Wait a bit for listener to process messages
+	time.Sleep(2 * time.Second)
 }