Bouton PDF par chapitre, badges morceaux améliorés, PDF configurable admin, git sync admin→prod

- Bouton PDF blanc par chapitre avec numéro de page (ChapterHeader)
- Badges morceaux plus visibles (bordure, poids, hover) dans ChapterHeader et SongBadges
- PDF viewer : page cible + panneau signets ouverts par défaut (BookPdfReader)
- Config YAML : pdfFile dans book, chapterPages pour le mapping chapitre→page
- Admin book : section PDF du livre avec chemin éditable et sauvegarde
- Git sync automatique : chaque sauvegarde admin commit+push en prod (ADMIN_GIT_SYNC=true)
- Docker : git installé en prod, volumes pour .git/site/content/public

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

app/components/book/ChapterHeader.vue

@@ -20,13 +20,24 @@
       <button
         v-for="song in songs"
         :key="song.id"
-        class="inline-flex items-center gap-1.5 rounded-full bg-primary/10 px-3 py-1 text-xs font-medium text-primary transition-colors hover:bg-primary/20"
+        class="song-badge-btn"
         @click="playSong(song)"
       >
         <div class="i-lucide-music h-3 w-3" />
         {{ song.title }}
       </button>
     </div>
+
+    <!-- PDF button -->
+    <div v-if="pdfPage" class="mt-3">
+      <button class="pdf-btn" @click="showPdf = true">
+        <div class="i-lucide-book-open h-3.5 w-3.5" />
+        <span>Lire dans le PDF</span>
+        <span class="pdf-page-badge">p.{{ pdfPage }}</span>
+      </button>
+    </div>
+
+    <BookPdfReader v-model="showPdf" :page="pdfPage" />
   </header>
 </template>
 
@@ -47,6 +58,9 @@ const { loadAndPlay } = useAudioPlayer()
 await bookData.init()
 
 const songs = computed(() => bookData.getChapterSongs(props.chapterSlug))
+const pdfPage = computed(() => bookData.getChapterPage(props.chapterSlug))
+
+const showPdf = ref(false)
 
 function playSong(song: Song) {
   loadAndPlay(song)
@@ -59,4 +73,57 @@ function playSong(song: Song) {
   padding-bottom: 0.75rem;
   border-bottom: 2px solid hsl(var(--color-primary) / 0.4);
 }
+
+.song-badge-btn {
+  display: inline-flex;
+  align-items: center;
+  gap: 0.375rem;
+  border-radius: 9999px;
+  padding: 0.375rem 0.875rem;
+  font-size: 0.8rem;
+  font-weight: 600;
+  background: hsl(var(--color-primary) / 0.12);
+  color: hsl(var(--color-primary) / 0.85);
+  border: 1px solid hsl(var(--color-primary) / 0.25);
+  cursor: pointer;
+  transition: all 0.2s;
+}
+
+.song-badge-btn:hover {
+  background: hsl(var(--color-primary) / 0.2);
+  border-color: hsl(var(--color-primary) / 0.4);
+  box-shadow: 0 2px 8px hsl(var(--color-primary) / 0.15);
+  transform: translateY(-1px);
+}
+
+.pdf-btn {
+  display: inline-flex;
+  align-items: center;
+  gap: 0.5rem;
+  padding: 0.5rem 1rem;
+  border-radius: 0.5rem;
+  background: hsl(0 0% 96%);
+  color: hsl(0 0% 15%);
+  font-size: 0.8rem;
+  font-weight: 600;
+  border: 1px solid hsl(0 0% 88%);
+  cursor: pointer;
+  transition: all 0.2s;
+}
+
+.pdf-btn:hover {
+  background: white;
+  box-shadow: 0 2px 12px hsl(0 0% 100% / 0.25);
+  transform: translateY(-1px);
+}
+
+.pdf-page-badge {
+  font-family: var(--font-mono, monospace);
+  font-size: 0.7rem;
+  font-weight: 500;
+  padding: 0.1rem 0.4rem;
+  border-radius: 0.25rem;
+  background: hsl(0 0% 88%);
+  color: hsl(0 0% 35%);
+}
 </style>