feat: refactor cart and bundle handling to support Buyable interface for improved flexibility

app/Domains/Shared/Contracts/Buyable.php

@@ -0,0 +1,20 @@
+<?php
+
+namespace App\Domains\Shared\Contracts;
+
+interface Buyable
+{
+    public function getPrice(): float;
+
+    public function getName(): string;
+
+    public function availableQuantity(): ?int;
+
+    public function reserveStock(int $amount): void;
+
+    public function decrementReservedStock(int $amount): void;
+
+    public function buy(int $amount): void;
+
+    public function validateStock(): void;
+}

app/Domains/Shared/Contracts/Stockable.php

@@ -1,15 +0,0 @@
-<?php
-
-namespace App\Domains\Shared\Contracts;
-
-interface Stockable
-{
-    public function incrementRealStock(int $amount): void;
-    public function decrementRealStock(int $amount): void;
-    
-    public function incrementReservedStock(int $amount): void;
-    public function decrementReservedStock(int $amount): void;
-    public function confirmReservedStock(int $amount): void;
-    
-    public function validateStock(): void;
-}