fix: resolve RedisCache array offset error and improve discovery diagnostics

- Fix RedisCache driver to handle MGET failures gracefully with fallback
- Add comprehensive discovery context comparison debug tools
- Identify root cause: WEB context discovery missing 166 items vs CLI
- WEB context missing RequestFactory class entirely (52 vs 69 commands)
- Improved exception handling with detailed binding diagnostics

src/Application/Shopify/ProductController.php

@@ -10,19 +10,12 @@ use App\Framework\Http\Method;
 use App\Framework\Http\Status;
 use App\Framework\Router\Result\JsonResult;
 use App\Infrastructure\Api\ShopifyClient;
-use Archive\Config\ApiConfig;
 
-final class ProductController
+final readonly class ProductController
 {
-    private ShopifyClient $client;
-
-    public function __construct()
-    {
-        $this->client = new ShopifyClient(
-            ApiConfig::SHOPIFY_SHOP_DOMAIN->value,
-            ApiConfig::SHOPIFY_ACCESS_TOKEN->value,
-            ApiConfig::SHOPIFY_API_VERSION->value
-        );
+    public function __construct(
+        private readonly ShopifyClient $client
+    ) {
     }
 
     /**