Zapier integration (#491)

* create zapier app

* install sanctum

* move OAuthProviderController

* make `api-external` middleware

* add zapier endpoints

* add tests

* token management

* zapier event handler

* add policy

* use `slug` instead of `id`

* wip

* check policies

* change api prefix to `external`

* ui tweaks

* validate token abilities

* open zapier URL

* zapier ui tweaks

* update zap

* Fix linting

* Added sample endpoints + minor UI changes

* Run PHP code linter

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Co-authored-by: Julien Nahum <julien@nahum.net>

app/Policies/PersonalAccessTokenPolicy.php

@@ -0,0 +1,14 @@
+<?php
+
+namespace App\Policies;
+
+use App\Models\User;
+use Laravel\Sanctum\PersonalAccessToken;
+
+class PersonalAccessTokenPolicy
+{
+    public function delete(User $user, PersonalAccessToken $token)
+    {
+        return $token->tokenable()->is($user);
+    }
+}