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/InfiniteReader.vue

@@ -6,13 +6,10 @@
         </div>
 
         <div v-for="(page, index) in pages" :key="index" class="page-wrapper">
-            <div v-if="page?.loading" class="loading">
+            <div v-if="!page?.url" class="loading">
                 <div class="animate-spin rounded-full h-12 w-12 border-b-2 border-blue-600"></div>
             </div>
-            <div v-else-if="page?.error" class="error">
-                {{ page.error }}
-            </div>
-            <ReaderPage v-else-if="page?.base64Content" :page-data="page" :page-number="index + 1" :zoom="zoom" :double-page-mode="doublePageMode" />
+            <ReaderPage v-else :page-data="page" :page-number="index + 1" :zoom="zoom" :double-page-mode="doublePageMode" loading="lazy" />
         </div>
 
         <!-- Navigation en bas -->