refactor: reorganise Service/ into Provider/ and Renderer/ sub-namespaces

Move all provider-related classes, enums, interface and trait into
App\Service\Provider; move SvgRenderer into App\Service\Renderer.
ContributionAggregator stays at the Service root as the orchestrator.
Test namespaces and use statements updated to match.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/Service/Provider/ProbeTrait.php

@@ -0,0 +1,63 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Service\Provider;
+
+use Symfony\Contracts\HttpClient\Exception\HttpExceptionInterface;
+use Symfony\Contracts\HttpClient\Exception\TransportExceptionInterface;
+
+trait ProbeTrait
+{
+    public function probe(): ProviderStatus
+    {
+        if (!$this->isConfigured()) {
+            return new ProviderStatus($this->getName(), ProviderStatusType::NotConfigured);
+        }
+
+        try {
+            $this->ping();
+
+            return new ProviderStatus($this->getName(), ProviderStatusType::Ok);
+        } catch (\Throwable $e) {
+            return $this->statusFromException($e);
+        }
+    }
+
+    private function statusFromException(\Throwable $e): ProviderStatus
+    {
+        [$error, $message] = $this->classifyException($e);
+
+        return new ProviderStatus($this->getName(), ProviderStatusType::Error, $error, $message);
+    }
+
+    /** @return array{ProviderErrorCode, string} */
+    private function classifyException(\Throwable $e): array
+    {
+        if ($e instanceof TransportExceptionInterface) {
+            return [ProviderErrorCode::UrlUnreachable, 'Could not reach the server: ' . $e->getMessage()];
+        }
+
+        if ($e instanceof HttpExceptionInterface) {
+            $code = $e->getResponse()->getStatusCode();
+
+            return match (true) {
+                $code === 401 => [ProviderErrorCode::AuthFailed, 'Invalid or expired token — verify your credentials'],
+                $code === 403 => [ProviderErrorCode::AuthFailed, 'Access denied — token lacks the required scopes'],
+                $code === 404 => [ProviderErrorCode::UrlUnreachable, 'Endpoint not found — check the configured URL'],
+                default       => [ProviderErrorCode::Unknown, "HTTP {$code}: " . $e->getMessage()],
+            };
+        }
+
+        $msg   = $e->getMessage();
+        $lower = strtolower($msg);
+        $error = match (true) {
+            str_contains($msg, 'not found') || str_contains($msg, 'Could not resolve') => ProviderErrorCode::UserNotFound,
+            str_contains($msg, 'GraphQL error')
+                && (str_contains($lower, 'unauthorized') || str_contains($lower, 'bad credentials')) => ProviderErrorCode::AuthFailed,
+            default => ProviderErrorCode::Unknown,
+        };
+
+        return [$error, $msg];
+    }
+}