fix exception with multi guard auth & filament multipanel

[bogusbd]

FIX TypeError

Filament\FilamentManager::getUserName(): Argument #1 ($user) must be of type Illuminate\Database\Eloquent\Model|Illuminate\Contracts\Auth\Authenticatable, null given, called in /var/www/html/vendor/laravel/framework/src/Illuminate/Support/Facades/Facade.php on line 355

The error can be reproduced as follows:

1. Create 2 guards /config/auth.php

    'guards' => [
        'web' => [
            'driver' => 'session',
            'provider' => 'users',
        ],
        'company' => [
            'driver' => 'session',
            'provider' => 'users',
        ],
    ],

2. One panel uses the default guard. Second custom, like this

    public function panel(Panel $panel): Panel
    {
        return $panel
           // ......
            ->path('company')
            ->authGuard('company')
            // ......
            ;
    }

3. From default guards try to impersonate.

    public static function table(Table $table): Table
    {
        return $table
             // .....
            ->actions([
                Impersonate::make('Login as')->guard('company')->redirectTo('/company/'),
            ])
    }

4. Open the URL for the default guard ... and you will see an Exception

Perhaps this can be fixed through the config /config/filament-impersonate.php but I'm not sure.

[jszobody]

@bogusbd It looks like you're making this fall back to empty string. Is that really the best option?

I don't have any multi-panel apps like this, but it seems like you'd still want the accurate user name to be displayed. Is it possible instead to pull the current user from the correct Filament authGuard?

Since you specify guard('company') perhaps we need to look at making sure the banner uses this guard when retrieving the user. I haven't dug into it yet. Does that seem reasonable?