Support PSR-18 clients

[simPod]

Is your feature request related to a problem? Please describe.

Dropping guzzle as a dependency in v0.8.0 is a nice step forward but two steps need to be done actually.

I have tons of PSR-18 client implementations available but in this lib I'm required to implement Spawnia\Sailor\Client instead which kind of reinvents the wheel.

Describe the solution you'd like

Accept PSR-compatible clients instead.

Doing this now which is a bit cumbersome

        return new class ($client) implements Client {
                public function __construct(private ClientInterface $client)
                {
                }

                public function request(string $query, \stdClass $variables = null) : Response
                {
                    $psr17Factory = new Psr17Factory();
                    $requestFactory = new GraphQLRequestFactory($psr17Factory, $psr17Factory);

                    /** @var array<string, mixed> $variablesArray */
                    $variablesArray = (array) $variables;

                    $request = $requestFactory->createRequest('', $query, $variablesArray);
                    $response = $this->client->sendRequest($request);

                    return Response::fromResponseInterface($response);
                }
            };

[spawnia]

How about we implement something like your example snippet in Spawnia\Sailor\Client\Psr18?

[simPod]

yup. that might work as well but what would be the reason to keep the Spawnia\Sailor\Client interface? It already returns PSR response 🤔

[spawnia]

It already returns PSR response 🤔

It returns GraphQL\Sailor\Response.

Here is an example of a client implementation that has nothing to do with PSR-18 or even HTTP: https://github.com/spawnia/sailor/blob/master/src/Client/Log.php
GraphQL itself is transport-agnostic.

[simPod]

Ah right and I forgot I use this util Response::fromResponseInterface($response). Kk, this makes the most sense #27 (comment) I'll implement it I guess.

[spawnia]

I am happy to accept a merge request for this and would like to keep this issue until something has landed.

[spawnia]

Supported as of https://github.com/spawnia/sailor/releases/tag/v0.9.0