feat: Implement inventory policy for product variants

- Introduced InventoryPolicy enum to manage tracked and unlimited inventory types.
- Updated ProductVariant model to include inventory_policy and cantidad_vendida attributes.
- Modified addItem and updateItem methods in Cart to check available quantity based on inventory policy.
- Added migration to include inventory_policy and cantidad_vendida in productos_variantes table.
- Enhanced tests to validate inventory behavior for both tracked and unlimited policies.
- Updated various request and resource classes to handle new inventory fields.

app/Domains/Catalog/Resources/ProductResource.php

@@ -35,7 +35,9 @@ class ProductResource extends JsonResource
             'variants_map' => $this->whenLoaded('variants', fn () => $this->variants
                 ->map(fn ($variant) => [
                     'variant_id' => $variant->id,
+                    'inventory_policy' => $variant->inventory_policy->value,
                     'cantidad_maxima' => $variant->stock_tecnico,
+                    'cantidad_vendida' => $variant->cantidad_vendida,
                     'attributes' => $variant->definitions
                         ->mapWithKeys(fn ($definition) => [
                             $definition->productAttribute?->attribute?->codigo => $definition->value,

app/Domains/Catalog/Resources/ProductVariantResource.php

@@ -18,7 +18,9 @@ class ProductVariantResource extends JsonResource
     {
         return [
             'id' => $this->id,
+            'inventory_policy' => $this->inventory_policy->value,
             'cantidad_maxima' => $this->stock_tecnico,
+            'cantidad_vendida' => $this->cantidad_vendida,
             'has_tickets' => $this->has_tickets,
             'minimum_use_date' => $this->minimum_use_date,
             'maximum_use_date' => $this->maximum_use_date,