Generate OpenAPI schema for error responses

[c1tru55]

Description

API platform should know default structure of own error responses, see:

\ApiPlatform\State\ApiResource\Error
\ApiPlatform\Validator\Exception\ValidationException

but don't generate schema for it. as a result you can't generate models for it and automatically map error responses in external apps.

Example

https://symfony-devs.slack.com/archives/C39FKU9AL/p1736882842918879?thread_ts=1736854101.898269&cid=C39FKU9AL