Filament: Registration and Login with Username or Email

To start with this, we have to add a custom login and registration page to our Panel Provider:

app/Providers/Filament/AdminPanelProvider.php

 
use App\Filament\Pages\Login;
use App\Filament\Pages\Register;
 
// ...
 
class AdminPanelProvider extends PanelProvider
{
    public function panel(Panel $panel): Panel
    {
        return $panel
            ->default()
            ->id('admin')
            ->path('admin')
            ->login(Login::class)
            ->registration(Register::class)
            ->colors([
                'primary' => Color::Amber,
            ])