Laravel Spark: Allow invited users to register without requirement for plan

register-common.blade.php

// resources/views/vendor/spark/auth/register-common.blade.php
// Add this check for invitation

<!-- Plan Selection -->
<div class="row" v-if="paidPlans.length > 0 && !invitation">

register-stripe.js

//resources/assets/js/spark-components/auth/register-stripe.js

methods: {
      /**
       * [Overriding Vendor's registration method] Attempt to register with the application.
       */
      register() {
          this.cardForm.errors.forget();

          this.registerForm.busy = true;
          this.registerForm.errors.forget();

          if(this.invitation != null) {
            return this.sendRegistration();
          }

          if ( ! Spark.cardUpFront || this.registerForm.invitation || this.selectedPlan.price == 0) {
              return this.sendRegistration();
          }

          Stripe.card.createToken(this.stripePayload(), (status, response) => {
              if (response.error) {
                  this.cardForm.errors.set({number: [response.error.message]})
                  this.registerForm.busy = false;
              } else {
                  this.registerForm.stripe_token = response.id;
                  this.sendRegistration();
              }
          });
      },
}

RegisterRequest.php

// app/Http/Requests/RegisterRequest.php
// Create this new request that registrations will go through
<?php

namespace App\Http\Requests;

use Laravel\Spark\Spark;
use App\Http\Requests\Request;
use Laravel\Spark\Contracts\Interactions\Auth\CreateUser;
use Laravel\Spark\Http\Requests\Auth\StripeRegisterRequest;

class RegisterRequest extends StripeRegisterRequest
{

    public function plan()
    {
        if ($this->plan) {
            return Spark::plans()->merge(Spark::teamPlans())->where('id', $this->plan)->first();
        }
    }

    public function baseValidator()
    {
        $validator = Spark::interact(
            CreateUser::class.'@validator', [$this]
        );

        $allPlanIdList = Spark::activePlanIdList().','.Spark::activeTeamPlanIdList();

        $validator->sometimes('plan', 'required|in:'.$allPlanIdList, function () {
            return Spark::needsCardUpFront() && ! $this->invitation;
        });

        return $validator;
    }
}

SparkServiceProvider.php

// app/Providers/SparkServiceProvider.php
// Register this new request
public function register()
{
    $this->app->singleton(RegisterRequestContract::class, RegisterRequest::class);
}