Add container-based search transformers to allow config serialization

[tomhelmer]

Bug Description

When Laravel serializes the config closures in the config file will break the serialization.

error: Your configuration files are not serializable.

Change introduced in : statamic/cms#2462

See: laravel/framework#9625

How to Reproduce

• Add transformer to search
• Run php artisan optimize

Environment

Statamic 3.0.20 Pro
Laravel 7.28.4
PHP 7.4.9

[tomhelmer]

A solution could be to add a searchTransformer service provider so site and addon developers can add transformers like :

app(searchTransformer::class)->extend(
  'myTransformer', 
  function ($data) { return someFunc($data); }
);

And then in search.php :

'transformers' => [
    'somefield' => 'myTransformer'
]

[github-actions]

This issue has not had recent activity and has been marked as stale — by me, a robot. Simply reply to keep it open and send me away. If you do nothing, I will close it in a week. I have no feelings, so whatever you do is fine by me.

[K3CK]

This still would be great!