Implement localization for API responses and error messages

- Added localization support for API responses in English and Spanish.
- Introduced a middleware to set the API locale based on the Accept-Language header.
- Updated various exception messages and validation responses to use localized strings.
- Created new language files for English and Spanish translations.
- Refactored existing code to replace hardcoded messages with localized strings.
- Added tests to verify localization functionality and response correctness.

app/Domains/Cart/Controllers/CartController.php

@@ -36,7 +36,10 @@ class CartController extends Controller
         );
 
         $response = CartResource::make($result['cart'])
-            ->additional(['message' => 'Producto agregado al carrito.'])
+            ->additional([
+                'code' => 'cart.item_added',
+                'message' => __('api.cart.item_added'),
+            ])
             ->response();
 
         if ($result['guest_token'] !== null) {
@@ -58,13 +61,19 @@ class CartController extends Controller
                 $cartItem->getKey(),
                 (int) $request->validated('cantidad'),
             )
-        )->additional(['message' => 'Cantidad de producto actualizada.']);
+        )->additional([
+            'code' => 'cart.quantity_updated',
+            'message' => __('api.cart.quantity_updated'),
+        ]);
     }
 
     public function removeItem(Request $request, Tenant $tenant, CartItem $cartItem): CartResource
     {
         return CartResource::make(
             $this->cartService->removeItem($tenant, $request, $cartItem->getKey())
-        )->additional(['message' => 'Producto eliminado del carrito.']);
+        )->additional([
+            'code' => 'cart.item_removed',
+            'message' => __('api.cart.item_removed'),
+        ]);
     }
 }

app/Domains/Cart/Models/Cart.php

@@ -79,7 +79,7 @@ class Cart extends Model
     {
         if ($quantity <= 0) {
             throw ValidationException::withMessages([
-                'cantidad' => 'La cantidad debe ser mayor a cero.',
+                'cantidad' => __('api.cart.positive_quantity'),
             ]);
         }
 
@@ -91,7 +91,7 @@ class Cart extends Model
 
             if ($availableQuantity !== null && $availableQuantity < $quantity) {
                 throw ValidationException::withMessages([
-                    'cantidad' => "Stock insuficiente para el producto solicitado. Maximo disponible: {$availableQuantity}.",
+                    'cantidad' => __('api.cart.insufficient_stock', ['max' => $availableQuantity]),
                 ]);
             }
 
@@ -123,7 +123,7 @@ class Cart extends Model
     {
         if ($quantity <= 0) {
             throw ValidationException::withMessages([
-                'cantidad' => 'La cantidad debe ser mayor a cero.',
+                'cantidad' => __('api.cart.positive_quantity'),
             ]);
         }
 
@@ -146,7 +146,7 @@ class Cart extends Model
             if ($delta > 0 && $availableQuantity !== null && $availableQuantity < $delta) {
                 $maxAvailable = $availableQuantity + $item->cantidad;
                 throw ValidationException::withMessages([
-                    'cantidad' => "El máximo que se puede agregar es {$maxAvailable}.",
+                    'cantidad' => __('api.cart.max_quantity', ['max' => $maxAvailable]),
                 ]);
             }
 
@@ -209,13 +209,13 @@ class Cart extends Model
         if ($catalogItem->isBundle()) {
             if ($variantId !== null) {
                 throw ValidationException::withMessages([
-                    'variant_id' => 'Un bundle no admite una variante.',
+                    'variant_id' => __('api.cart.bundle_variant_forbidden'),
                 ]);
             }
 
             if (! $catalogItem->bundleComponents()->exists()) {
                 throw ValidationException::withMessages([
-                    'catalog_item_id' => 'El bundle no tiene componentes.',
+                    'catalog_item_id' => __('api.cart.empty_bundle'),
                 ]);
             }
 
@@ -225,7 +225,7 @@ class Cart extends Model
         if ($variantId === null) {
             if ($catalogItem->inventory_id === null) {
                 throw ValidationException::withMessages([
-                    'variant_id' => 'Debe seleccionar una variante para este ítem.',
+                    'variant_id' => __('api.cart.variant_required'),
                 ]);
             }