Agregue middleware a productos Destroy y Edit. Y cambios en la vista de stock.

app/Http/Middleware/CheckAdmin.php

@@ -0,0 +1,19 @@
+<?php
+
+namespace App\Http\Middleware;
+
+use Closure;
+use Illuminate\Http\Request;
+use Symfony\Component\HttpFoundation\Response;
+
+class CheckAdmin // 
+{
+    public function handle(Request $request, Closure $next): Response
+    {
+        if (auth()->check() && auth()->user()->role === 'admin') {
+            return $next($request);
+        }
+
+        abort(403, 'No tienes permiso para entrar aquí.');
+    }
+}