Fix: Turning the bind of the ShippingMethodManagerInterface to a singleton, so that it can actually resolve the shipping methods

src/Providers/ShippingServiceProvider.php

@@ -154,7 +154,13 @@ class ShippingServiceProvider extends ServiceProvider
         // run before the Shipping::extend() calls below, which resolve —
         // and the facade then CACHES — whatever's bound at that moment).
         $this->app->booted(function () {
-            $this->app->bind(ShippingMethodManagerInterface::class, fn ($app) => $app->make(ShippingManager::class));
+            // A singleton, not bind(): the queue worker clears every
+            // facade's cached instance before each job
+            // (Facade::clearResolvedInstances()), so with bind() the Shipping
+            // facade then built a fresh, empty manager — without the drivers
+            // extended below — and every queued job (tracking, voucher sync)
+            // saw no carriers at all.
+            $this->app->singleton(ShippingMethodManagerInterface::class, fn ($app) => $app->make(ShippingManager::class));
 
             // Shipping::extend('acs', fn ($app) => $app->make(AcsRateDriver::class));
             Shipping::extend('box-now', fn ($app) => $app->make(BoxNowRateDriver::class));