feat(documents): migrate storage to filesystem, add server-side pagination

- Replace Base64 data URIs with file-based storage served via dedicated endpoints
- Add DocumentPreviewModal navigation, DocumentThumbnail fileUrl support
- Refactor documents page with server-side pagination, search, sort and filters
- Update all components to use fileUrl/downloadUrl instead of raw path
- Add pagination composable support (total, page, itemsPerPage, attachmentFilter)

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

app/pages/component/[id]/edit.vue

@@ -2,6 +2,7 @@
   <DocumentPreviewModal
     :document="previewDocument"
     :visible="previewVisible"
+    :documents="componentDocuments"
     @close="closePreview"
   />
   <main class="container mx-auto px-6 py-10">
@@ -386,8 +387,8 @@
                   :class="documentThumbnailClass(document)"
                 >
                   <img
-                    v-if="isImageDocument(document) && document.path"
-                    :src="document.path"
+                    v-if="isImageDocument(document) && (document.fileUrl || document.path)"
+                    :src="document.fileUrl || document.path"
                     class="h-full w-full object-cover"
                     :alt="`Aperçu de ${document.name}`"
                   >