Filament Menu "Paywall": Show Items but Restrict Access

It's inspired by a question on the official Filament Discord:

So, this project shows four Filament Resources:

• Tasks (free)
• Projects, Tags, Categories (paid)

Notice 1: The project doesn't implement the payments/subscriptions. It's simplified and focused on just menu items show/hide, using just users.is_subscribed DB column.

Notice 2: those resources are also "placeholders", without any DB data or Filament columns/inputs, just to show the situation.

If a non-subscribed user clicks on any Paid resource, they are redirected to the speficic Locked page, with the resource as a part of the URL, for future redirect after the payment.

To check each page for access, there's a global SubscriptionMiddleware assigned to all Filament routes.

app/Http/Middleware/SubscriptionMiddleware.php:

class SubscriptionMiddleware
{
    private array $paidResources = [
        'tags',
        'projects',
        'categories',
    ];
 
    /**
     * Handle an incoming request.
     *
     * @param  \Closure(\Illuminate\Http\Request): (\Symfony\Component\HttpFoundation\Response)  $next
     */
    public function handle(Request $request, Closure $next): Response
    {
        if (!auth()->user()->is_subscribed) {
            // ...