refactor(reader): serve pages as static files instead of base64

Replace the per-page API call (base64 payload) with static image URLs
served directly by Caddy from public/images/pages/{chapterId}/.

- LocalImageStorage now stores to public/images/ (was MANGA_DATA_PATH)
- LegacyChapterRepository returns /images/pages/{id}/{file} URLs,
  uses getimagesize() instead of loading file content into memory
- Delete GetChapterPage query/handler/response, ChapterPageResource,
  ChapterPageProvider, PageContent model
- Remove getPageContent() from ChapterRepositoryInterface
- Frontend: loadChapter() fetches chapter + all pages in parallel,
  ReaderPage uses URL instead of base64 data URI, InfiniteReader drops
  lazy-load observer side effect, readerStore drops loadedPages/preload
- GetChapterPagesTest: extract fixture images from CBZ at runtime,
  ignore tests/Fixtures/pages/ in .gitignore

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

assets/vue/app/domain/reader/presentation/components/ReaderPage.vue

@@ -1,7 +1,7 @@
 <template>
     <div class="page-container" :style="{ transform: `scale(${zoom})` }">
         <div v-if="!pageData" class="error">Aucune donnée d'image disponible</div>
-        <div v-else-if="!pageData.base64Content" class="error">Contenu de l'image manquant</div>
+        <div v-else-if="!pageData.url" class="error">URL de l'image manquante</div>
 
         <!-- Affichage spécial pour les doubles pages sur mobile -->
         <div v-else-if="isDoublePage && isMobile && doublePageMode !== 'normal'" class="double-page-mobile">
@@ -88,10 +88,7 @@ import { useReaderStore } from '../../application/store/readerStore';
     const imageLoaded = ref(false);
 
     const imageSource = computed(() => {
-        if (!props.pageData?.base64Content || !props.pageData?.mimeType) {
-            return '';
-        }
-        return `data:${props.pageData.mimeType};base64,${props.pageData.base64Content}`;
+        return props.pageData?.url ?? '';
     });
 
     // Détection des doubles pages basée sur le ratio largeur/hauteur et les dimensions API