I broke Laravel!! - help!!

To answer all the questions...

No, there's no artisan run:migrate command, that was just my dumb mistake. But thereafter noting will run because of this "can't find dusk" error. I never got to run the migration as everything including artisan broke.

I'm working on a clone of an existing L6 site that uses an old version of stripe-php. I'm in the process of rewriting the ecommerce code to use Stripe Checkout in advance of an upgrade, which is where this broke. I didn't get to my first commit so my "backup" would be to re-clone the original site. I'm not too far from that, so I could go back to square one and keep the new .ENV to quickly get the local connections back, but I was hoping someone would recognize the issue and say "oh yeah, you must have changed xxx. Change it back and all will be well again." I also hate going back via retore when I don't know what the issue is - it remains a nagging mystery.

It looks like the offending line in index.php is

$response = $kernel->handle(
    $request = Illuminate\Http\Request::capture()
);

which reports the following error and cascades from there:

Class 'Laravel\Dusk\DuskServiceProvider' not found
(1/1) Error
Class 'Laravel\Dusk\DuskServiceProvider' not found

in Application.php line 679
at Application->resolveProvider('Laravel\Dusk\DuskServiceProvider')
in Application.php line 613
at Application->register('Laravel\Dusk\DuskServiceProvider')
in ProviderRepository.php line 75
at ProviderRepository->load(array('Illuminate\Auth\AuthServiceProvider', 'Illuminate\Broadcasting\BroadcastServiceProvider', 'Illuminate\Bus\BusServiceProvider', 'Illuminate\Cache\CacheServiceProvider', 'Illuminate\Foundation\Providers\ConsoleSupportServiceProvider', 'Illuminate\Cookie\CookieServiceProvider', 'Illuminate\Database\DatabaseServiceProvider', 'Illuminate\Encryption\EncryptionServiceProvider', 'Illuminate\Filesystem\FilesystemServiceProvider', 'Illuminate\Foundation\Providers\FoundationServiceProvider', 'Illuminate\Hashing\HashServiceProvider', 'Illuminate\Mail\MailServiceProvider', 'Illuminate\Notifications\NotificationServiceProvider', 'Illuminate\Pagination\PaginationServiceProvider', 'Illuminate\Pipeline\PipelineServiceProvider', 'Illuminate\Queue\QueueServiceProvider', 'Illuminate\Redis\RedisServiceProvider', 'Illuminate\Auth\Passwords\PasswordResetServiceProvider', 'Illuminate\Session\SessionServiceProvider', 'Illuminate\Translation\TranslationServiceProvider', 'Illuminate\Validation\ValidationServiceProvider', 'Illuminate\View\ViewServiceProvider', 'Aloha\Twilio\Support\Laravel\ServiceProvider', 'Barryvdh\DomPDF\ServiceProvider', 'Biscolab\ReCaptcha\ReCaptchaServiceProvider', 'Fideloper\Proxy\TrustedProxyServiceProvider', 'hisorange\BrowserDetect\ServiceProvider', 'Intervention\Image\ImageServiceProvider', 'Lab404\Impersonate\ImpersonateServiceProvider', 'Laravel\Dusk\DuskServiceProvider', 'Laravel\Tinker\TinkerServiceProvider', 'Collective\Html\HtmlServiceProvider', 'Laravelista\Comments\ServiceProvider', 'Maatwebsite\Excel\ExcelServiceProvider', 'Mpociot\Teamwork\TeamworkServiceProvider', 'Carbon\Laravel\ServiceProvider', 'Spatie\Honeypot\HoneypotServiceProvider', 'Spatie\MediaLibrary\MediaLibraryServiceProvider', 'Spatie\StripeWebhooks\StripeWebhooksServiceProvider', 'Spatie\WebhookClient\WebhookClientServiceProvider', 'Yajra\DataTables\DataTablesServiceProvider', 'YbrNX\MariaDB\MariaDBServiceProvider', 'PHPJasper\PHPJasperServiceProvider', 'Laravel\Tinker\TinkerServiceProvider', 'Intervention\Image\ImageServiceProvider', 'Collective\Html\HtmlServiceProvider', 'Yajra\DataTables\DataTablesServiceProvider', 'Spatie\MediaLibrary\MediaLibraryServiceProvider', 'Lab404\Impersonate\ImpersonateServiceProvider', 'Barryvdh\DomPDF\ServiceProvider', 'App\Providers\AppServiceProvider', 'App\Providers\AuthServiceProvider', 'App\Providers\EventServiceProvider', 'App\Providers\RouteServiceProvider', 'Barryvdh\DomPDF\ServiceProvider', 'Biscolab\ReCaptcha\ReCaptchaServiceProvider'))
in Application.php line 593
at Application->registerConfiguredProviders()
in RegisterProviders.php line 17
at RegisterProviders->bootstrap(object(Application))
in Application.php line 219
at Application->bootstrapWith(array('Illuminate\Foundation\Bootstrap\LoadEnvironmentVariables', 'Illuminate\Foundation\Bootstrap\LoadConfiguration', 'Illuminate\Foundation\Bootstrap\HandleExceptions', 'Illuminate\Foundation\Bootstrap\RegisterFacades', 'Illuminate\Foundation\Bootstrap\RegisterProviders', 'Illuminate\Foundation\Bootstrap\BootProviders'))
in Kernel.php line 156
at Kernel->bootstrap()
in Kernel.php line 140
at Kernel->sendRequestThroughRouter(object(Request))
in Kernel.php line 110
at Kernel->handle(object(Request))
in index.php line 55

I have checked and DuskServiceProvider.php is present in the vendor \laravel\dusk\src folder

The app and artisan were running fine right up until that erroneous command artisan run:migration and instantly this error breaks everything

Since dusk is to do with running in dev mode, would that have something to do with it?

Also, happy to share my code, just don't know what to share that relates to this. The migration I was creating at the time was never run as artisan broke before I got that far. Let me know if you can think of any code we should look at.