feat(manga): implémenter la page Découvrir avec recommandations MangaDex

- Endpoint GET /api/manga-discover via DiscoverMangaStateProvider + DiscoverMangaHandler
- Algorithme : top 5 manga de la collection → appel /manga/{id}/recommendation
  par source → agrégation avec système de votes (multi-sources = plus pertinent)
- Filtrage : tags exclus (Oneshot, Doujinshi, Self-Published), contentRating,
  et suppression des manga déjà en bibliothèque
- Page Vue DiscoverPage.vue : chargement auto au montage, bouton Actualiser,
  modal détail, ajout à la bibliothèque
- Adapteurs InMemory de test mis à jour (discover + getMangaRecommendations)

src/Domain/Manga/Infrastructure/ApiPlatform/Resource/MangaDiscoverResource.php

@@ -0,0 +1,22 @@
+<?php
+
+namespace App\Domain\Manga\Infrastructure\ApiPlatform\Resource;
+
+use ApiPlatform\Metadata\ApiResource;
+use ApiPlatform\Metadata\Get;
+use App\Domain\Manga\Infrastructure\ApiPlatform\Dto\MangaSearchCollection;
+use App\Domain\Manga\Infrastructure\ApiPlatform\State\Provider\DiscoverMangaStateProvider;
+
+#[ApiResource(
+    shortName: 'Mangadex',
+    operations: [
+        new Get(
+            uriTemplate: '/manga-discover',
+            output: MangaSearchCollection::class,
+            provider: DiscoverMangaStateProvider::class
+        )
+    ]
+)]
+class MangaDiscoverResource
+{
+}

src/Domain/Manga/Infrastructure/ApiPlatform/State/Provider/DiscoverMangaStateProvider.php

@@ -0,0 +1,41 @@
+<?php
+
+namespace App\Domain\Manga\Infrastructure\ApiPlatform\State\Provider;
+
+use ApiPlatform\Metadata\Operation;
+use ApiPlatform\State\ProviderInterface;
+use App\Domain\Manga\Application\Query\DiscoverManga;
+use App\Domain\Manga\Application\QueryHandler\DiscoverMangaHandler;
+use App\Domain\Manga\Infrastructure\ApiPlatform\Dto\MangaSearchCollection;
+use App\Domain\Manga\Infrastructure\ApiPlatform\Dto\MangaSearchItem;
+
+readonly class DiscoverMangaStateProvider implements ProviderInterface
+{
+    public function __construct(private DiscoverMangaHandler $handler)
+    {
+    }
+
+    public function provide(Operation $operation, array $uriVariables = [], array $context = []): MangaSearchCollection
+    {
+        $response = $this->handler->handle(new DiscoverManga());
+
+        return new MangaSearchCollection(
+            items: array_map(
+                fn ($item) => new MangaSearchItem(
+                    externalId: $item->externalId,
+                    title: $item->title,
+                    slug: $item->slug,
+                    description: $item->description,
+                    author: $item->author,
+                    publicationYear: $item->publicationYear,
+                    genres: $item->genres,
+                    status: $item->status,
+                    imageUrl: $item->imageUrl,
+                    thumbnailUrl: $item->thumbnailUrl,
+                    rating: $item->rating
+                ),
+                $response->items
+            )
+        );
+    }
+}

src/Domain/Manga/Infrastructure/Client/MangadexClient.php

@@ -127,6 +127,35 @@ class MangadexClient implements MangadexClientInterface
         ]);
     }
 
+    public function getMangaRecommendations(string $mangaId): array
+    {
+        // L'endpoint retourne des objets manga_recommendation avec des relationships
+        // vers les manga (sans détails). Il faut d'abord récupérer les IDs, puis
+        // fetcher les manga en batch avec leurs détails complets.
+        $recommendations = $this->get('/manga/' . $mangaId . '/recommendation');
+
+        $recommendedIds = [];
+        foreach ($recommendations['data'] ?? [] as $item) {
+            foreach ($item['relationships'] ?? [] as $rel) {
+                if ($rel['type'] === 'manga' && $rel['id'] !== $mangaId) {
+                    $recommendedIds[] = $rel['id'];
+                }
+            }
+        }
+
+        if (empty($recommendedIds)) {
+            return ['data' => []];
+        }
+
+        return $this->get('/manga', [
+            'ids'           => $recommendedIds,
+            'includes'      => ['cover_art', 'author'],
+            'contentRating' => ['safe', 'suggestive', 'erotica'],
+            'excludedTags'  => self::EXCLUDED_TAGS,
+            'limit'         => count($recommendedIds),
+        ]);
+    }
+
     private function get(string $endpoint, array $params = []): array
     {
         try {

src/Domain/Manga/Infrastructure/Provider/MangadexProvider.php

@@ -135,6 +135,55 @@ readonly class MangadexProvider implements MangaProviderInterface
         }
     }
 
+    public function discover(array $sourceExternalIds): MangaCollection
+    {
+        if (empty($sourceExternalIds)) {
+            return new MangaCollection([]);
+        }
+
+        // Compter les votes : un manga recommandé par plusieurs sources est plus pertinent.
+        // On conserve aussi la position d'apparition pour départager les ex-aequo.
+        $votes = [];
+        $firstPosition = [];
+        $resultsById = [];
+        $position = 0;
+
+        foreach ($sourceExternalIds as $externalId) {
+            try {
+                $response = $this->client->getMangaRecommendations($externalId);
+                foreach ($response['data'] ?? [] as $result) {
+                    $id = $result['id'];
+                    $votes[$id] = ($votes[$id] ?? 0) + 1;
+                    if (!isset($firstPosition[$id])) {
+                        $firstPosition[$id] = $position++;
+                        $resultsById[$id] = $result;
+                    }
+                }
+            } catch (\Exception) {
+                continue;
+            }
+        }
+
+        if (empty($resultsById)) {
+            return new MangaCollection([]);
+        }
+
+        // Trier : votes décroissants (multi-sources = plus pertinent), puis position croissante (score API)
+        uksort($resultsById, function (string $a, string $b) use ($votes, $firstPosition): int {
+            $voteDiff = $votes[$b] - $votes[$a];
+            if ($voteDiff !== 0) {
+                return $voteDiff;
+            }
+
+            return $firstPosition[$a] <=> $firstPosition[$b];
+        });
+
+        $mangas = $this->createMangasFromResults(array_values($resultsById));
+        $this->enrichWithRatings($mangas);
+
+        return new MangaCollection($mangas);
+    }
+
     public function findByExternalId(ExternalId $externalId): ?Manga
     {
         try {